



300mAh USB-C Battery for SRAM AXS / eTap – Carbon Fiber
Direct USB-C Charging. One Less Charger to Pack.
Make charging your electronic shifting system easier.
This aftermarket 300mAh rechargeable battery features an integrated USB-C charging port, allowing you to charge the battery directly without using a separate SRAM-style charging cradle.
Simply connect a compatible USB-C cable and power source directly to the battery.
Designed for compatible SRAM AXS / eTap rear derailleurs, it combines convenient direct charging, a lightweight carbon fiber housing, and multiple electrical protection features in one compact battery.
300mAh Rated Capacity
The battery is rated at:
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Capacity: 300mAh
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Voltage: 7.4V
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Energy: 2.22Wh
It can be used as a replacement or spare battery for compatible SRAM AXS / eTap rear derailleurs.
Actual operating time may vary depending on shifting frequency, temperature, battery condition, derailleur model, and riding conditions.
Approximately 20.5g Lightweight Design
The pictured 300mAh battery weighs approximately 20.5g.
The lightweight carbon fiber housing helps keep overall system weight low while maintaining a compact battery structure.
Actual weight may vary slightly depending on the carbon finish and production tolerances.
Two Carbon Fiber Finishes
Choose between two different exterior finishes:
3K Carbon Weave
Classic and uniform woven carbon fiber appearance.
Forged Carbon Pattern
Irregular forged-carbon-style pattern for a more distinctive appearance.
Due to the nature of carbon fiber materials and manufacturing, the exact pattern may vary slightly between individual batteries.
USB-C Direct Charging
The integrated USB-C charging port allows the battery to be charged directly without removing it and placing it into a separate charging cradle.
This means fewer accessories to carry when traveling or riding.
Simply connect a compatible USB-C charging cable and power source to begin charging.
PD / QC Compatible Power Source Support
According to the supplier, the charging system supports compatible PD and QC power sources.
Charging performance may vary depending on:
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Charger
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USB-C cable
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Battery state
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Power-source specifications
Support for PD or QC power sources does not necessarily mean that the battery will charge at the maximum fast-charging output of the charger.
Sealed Charging Structure
The battery uses a multi-layer sealing design intended to improve protection during everyday riding conditions.
When the battery is installed on the rear derailleur, the main external sealing surface is created between the battery and rear derailleur interface.
The sealing gasket is located on the rear derailleur side, similar to the original battery mounting structure.
This means the battery and derailleur work together to form the external seal when correctly installed.
Fully Potted Internal Electronics
Inside the battery, the charging-port area and internal electronic components are fully sealed with protective potting compound.
This construction helps isolate the internal circuitry from moisture and contaminants.
Unlike a simple exposed USB-C socket connected directly to the battery terminals, the internal electronics and charging interface are protected within the sealed battery structure.
This provides an additional layer of protection for real-world cycling use.
Smart USB-C Power-On Protection
The USB-C interface incorporates protocol-controlled power activation.
The charging port does not remain continuously powered.
Electrical output is enabled only after a compatible charging protocol is successfully detected and established.
This means that under normal conditions, simply having moisture or water inside the USB-C port does not automatically place the charging contacts under active power.
The design helps reduce the possibility of an electrical short circuit caused by moisture entering the USB-C charging interface during riding.
Protection Logic
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USB-C interface remains unpowered before protocol detection
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Compatible charging connection must be successfully established
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Power is activated only after protocol recognition
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Helps reduce the risk of moisture-related short circuits
Multi-Layer Moisture Protection
The battery therefore uses several complementary protection methods:
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Rear-derailleur interface sealing
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Derailleur-side sealing gasket
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Fully potted internal electronics
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Sealed internal charging circuitry
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Protocol-controlled USB-C power activation
Together, these features are designed to provide better protection against moisture encountered during normal cycling conditions.
Important: This product should not be considered completely waterproof or suitable for prolonged submersion. Always keep the USB-C port clean and dry whenever possible.
Integrated Battery Protection
According to the supplier, the built-in protection circuit includes:
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Overcharge protection
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Over-discharge protection
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Overcurrent protection
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High-temperature protection
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Low-temperature protection
These protection functions help manage battery operation and charging under normal use.
Always use and charge the battery according to the supplied instructions.
SPECIFICATIONS
Product Type: Aftermarket rechargeable rear derailleur battery
Intended Application: Compatible SRAM AXS / eTap rear derailleurs
Rated Capacity: 300mAh
Rated Voltage: 7.4V
Rated Energy: 2.22Wh
Charging Port: USB-C
Housing Material: Carbon fiber
Carbon Finish Options:
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3K Carbon Weave
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Forged Carbon Pattern
Reference Weight: Approximately 20.5g
Charging Power Source Support: Compatible PD / QC power sources according to the supplier
Internal Protection:
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Overcharge protection
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Over-discharge protection
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Overcurrent protection
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High-temperature protection
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Low-temperature protection
Moisture Protection Design:
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Rear-derailleur interface sealing
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Internally potted electronics
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Protocol-controlled USB-C power activation
COMPATIBILITY
Designed for compatible SRAM AXS / eTap rear derailleurs using this style of removable battery interface.
Because SRAM produces multiple generations and component variations, compatibility should not automatically be assumed across every SRAM AXS / eTap component.
Please confirm your exact rear derailleur model before ordering.
If you are unsure about compatibility, please contact us and provide:
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Your exact SRAM derailleur model
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A photo of the derailleur
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A photo of the original battery mounting area
We can help confirm compatibility before purchase.
Aftermarket Product Notice
This is an aftermarket replacement battery and is not an original SRAM product.
SRAM, AXS and eTap are trademarks of their respective owners and are used only to identify the intended compatibility and application of this product.
FREQUENTLY ASKED QUESTIONS
Do I need a separate charging cradle?
No.
The battery has a built-in USB-C charging port, so it can be charged directly using a compatible USB-C cable and power source.
What capacity is available?
This version is currently available in 300mAh.
How much does the battery weigh?
The pictured sample weighs approximately 20.5g.
Actual weight may vary slightly due to carbon finish and production tolerances.
What is the difference between 3K Carbon and Forged Carbon?
Both versions have the same listed 300mAh battery capacity.
The difference is primarily appearance.
3K Carbon Weave features a regular woven carbon pattern.
Forged Carbon Pattern features a more irregular and distinctive carbon appearance.
Can I use a PD or QC charger?
According to the supplier, compatible PD and QC power sources are supported.
Actual charging performance depends on the charger, cable, and battery charging system.
Compatibility with every charger and cable combination cannot be guaranteed.
How is the USB-C port protected from water?
When installed, the battery uses the rear derailleur interface as part of the external sealing structure, with the sealing gasket located on the derailleur side.
Inside the battery, the charging circuitry and USB-C interface area are additionally sealed using protective potting compound.
Will the USB-C port short circuit if water enters it?
The USB-C charging interface uses protocol-controlled power activation.
The port is not continuously powered and only becomes electrically active after a compatible charging protocol has been successfully detected.
This design helps reduce the risk of a short circuit if moisture enters the USB-C port during riding.
However, the product should not be treated as completely waterproof, and the charging port should always be kept as clean and dry as possible.
Can I leave the battery installed while charging?
Yes, the integrated USB-C port is designed to make direct charging more convenient.
Make sure the charging area is clean and dry before connecting the USB-C cable.
Is this an original SRAM battery?
No.
This is an aftermarket replacement battery designed for compatible SRAM AXS / eTap applications.
Important Usage Notes
Before charging, check that the USB-C port is clean and dry.
Do not charge the battery if:
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The charging port is visibly wet
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The battery housing is damaged
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The battery is swollen
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The USB-C connector is damaged
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The battery has been involved in a severe impact
Do not disassemble, puncture, crush, burn, or modify the battery.
Use a compatible, good-quality charging cable and power source.
If abnormal heat, swelling, odor, smoke, or charging behavior occurs, stop using the battery immediately.
Verificación de compatibilidad: debido a la complejidad de los modelos y lotes de piezas del fabricante de equipos originales (OEM), puede haber casos en los que este producto sea incompatible.
Al recibir este producto, compárelo con las especificaciones OEM para garantizar la compatibilidad antes de la instalación.
Especificaciones de torque: Instale este producto estrictamente de acuerdo con los valores de torque especificados en el manual de piezas OEM. Problemas de instalación: Si encuentra alguna discrepancia con las especificaciones OEM o enfrenta dificultades en la etapa inicial de instalación, deténgase inmediatamente y comuníquese con el servicio al cliente para obtener ayuda con devoluciones o cambios.
Sin instalación forzada: No fuerce la instalación bajo ninguna circunstancia. Responsabilidad: Cualquier daño resultante de una instalación forzada o modificaciones no autorizadas de este producto (o sus componentes) será responsabilidad exclusiva del comprador.
Todos los productos están fotografiados para representar con precisión los colores que verá al recibirlos.
Debido a diferencias de iluminación, ángulos o configuraciones de pantalla, pueden ocurrir ligeras variaciones de color.
El producto real debe considerarse el estándar. Para los productos "coloreados" y "azules", el proceso de coloración puede generar una distribución desigual del color, lo que hace que cada producto sea único.
| Tabla de referencia de par de torsión común de S-PARTS para series de bicicletas | ||||||
| Ingrediente | Nombre del componente | Nombre del tornillo | Par de referencia | Uso de antiadherentes | Uso de fijador de roscas de resistencia media | Requisitos especiales Observaciones |
| Sistema de marco | Conjunto del manillar | Tornillos de fijación del vástago M4 | 4 MN | Recomendado | Considere con precaución | Para conjuntos de manillares con estructuras especiales, consulte las especificaciones de torque recomendadas por el fabricante original. |
| Tornillos de fijación del vástago M5 | 5 Millas Náuticas | Recomendado | Considere con precaución | |||
| Tornillos de fijación del vástago M6 | 6-8 millas náuticas | Recomendado | Considere con precaución | |||
| Tornillos de fijación del manillar M7 (Brompton) | 8-10 millas náuticas | Recomendado | Considere con precaución | |||
| Tornillos de fijación de potencia M8 (BMX) | 8-10 millas náuticas | Recomendado | Considere con precaución | |||
| Auriculares | Tornillos de precarga de los auriculares (incluidos M5/M6) | 4-6 millas náuticas | Recomendado | No recomendado | ||
| Marco/horquilla | Tornillos de abrazadera de manguera de horquilla M3 | 1-2 MN | Recomendado | No recomendado | Para abrazaderas de tija de sillín con estructuras especiales, consulte las especificaciones de torque recomendadas por el fabricante original. | |
| Tornillos para portabotellas | 4NMM | Recomendado | No recomendado | |||
| Tornillos de fijación de la patilla del desviador M4 | 3-4 millas náuticas | Recomendado | Considere con precaución | |||
| Tornillos de fijación de la patilla del desviador M5 | 4-5 millas náuticas | Recomendado | Considere con precaución | |||
| Tornillos de fijación de bastidor delantero y trasero M5 | 6-7 millas náuticas | Recomendado | Considere con precaución | |||
| Tornillo de abrazadera de tija de sillín M5 (diseño de abrazadera estándar) | 6-7 millas náuticas | Recomendado | No recomendado | |||
| Tija de sillín | Tornillos de sujeción del riel del sillín M5 | 6-7 millas náuticas | Recomendado | No recomendado | ||
| Tornillos de sujeción del riel del sillín M6 | 7-9 millas náuticas | Recomendado | No recomendado | |||
| Tornillos de sujeción del riel del sillín M7 | 8-10 millas náuticas | Recomendado | No recomendado | |||
| Tornillos de abrazadera de riel de sillín de un solo perno M6/M7 | 10-12 millas náuticas | Recomendado | No recomendado | |||
| Tornillos de sujeción de riel de sillín de un solo perno M8 (Brompton) | 12-14 millas náuticas | Recomendado | No recomendado | |||
| Juego de ruedas | Tornillos de bloqueo para juego de ruedas de liberación rápida M6 | 6-8 millas náuticas | Recomendado | No recomendado | ||
| Tornillos de bloqueo para juego de ruedas BMX M10 | Recomendado | No recomendado | ||||
| Tornillos para juego de ruedas BMX M14 | Recomendado | No recomendado | ||||
| Tuercas de bloqueo para juego de ruedas M9 | 12-14 millas náuticas | Recomendado | No recomendado | |||
| Tuercas de bloqueo para juego de ruedas M10 | 14-16 millas náuticas | Recomendado | No recomendado | |||
| Perno de eje pasante M12 | 10-14 millas náuticas | Recomendado | No recomendado | |||
| Perno de eje pasante M14 | 12-16 millas náuticas | Recomendado | No recomendado | |||
| Sistema de frenos | Rotor de disco | Tornillos de rotor de disco de seis pernos | 5-7 millas náuticas | Considere con precaución | Recomendado | No utilice compuestos antiadherentes ni fijadores de roscas líquidos en los tornillos relacionados con el sistema hidráulico del freno para evitar contaminar las líneas hidráulicas. |
| Rotor de disco con bloqueo central | 40 millas náuticas | Recomendado | No recomendado | |||
| Palanca de freno | Tornillos de fijación de la palanca de freno M5 | 5-7 millas náuticas | Recomendado | No recomendado | ||
| Tornillos de fijación de la palanca de freno M6 | 6-8 millas náuticas | Recomendado | No recomendado | |||
| Tuercas de fijación para palanca de cambios de bicicleta de carretera | 6-8 millas náuticas | Recomendado | No recomendado | |||
| Tornillos del puerto de purga de la palanca de freno | 2-3 millas náuticas | No recomendado | Recomendado | |||
| Pinza de freno de disco | Tornillos de fijación de pinza de bicicleta de montaña M6 | 9 Millas Náuticas | Considere con precaución | Recomendado | ||
| Tornillos de fijación de pinza de montaje plano M5 | 7 Millas Náuticas | Considere con precaución | No recomendado | |||
| Tornillos de conexión por compresión de manguera M8 | 6-7 millas náuticas | No recomendado | No recomendado | |||
| Tornillos del cuerpo de la pinza M6 | 12 millas náuticas | No recomendado | No recomendado | |||
| Tornillos del cuerpo de la pinza M7 | 14 millas náuticas | No recomendado | No recomendado | |||
| Tornillos del cuerpo de la pinza M8 | 14 millas náuticas | No recomendado | No recomendado | |||
| Tornillos de banjo para calibrador M6 | 12 millas náuticas | No recomendado | No recomendado | |||
| Tornillos de purga de la pinza | 5-6 millas náuticas | No recomendado | No recomendado | |||
| Pasador de pastilla de freno | 3 MN | No recomendado | No recomendado | |||
| Pinza de freno tipo C | Tuerca de fijación de pinza de pivote simple | 8 MN | No recomendado | Recomendado | ||
| Tornillos de fijación de la pinza de pivote doble | 6-8 millas náuticas | Considere con precaución | Considere con precaución | |||
| Juego de tornillos de fijación de pastillas de freno | 7 Millas | Considere con precaución | Considere con precaución | |||
| Tornillos de tope de la pastilla de freno | 3 MN | No recomendado | No recomendado | |||
| Tornillos de la palanca de liberación de la pinza | 3 MN | No recomendado | No recomendado | |||
| Tornillos de anclaje para cables | 5-7 millas náuticas | Recomendado | No recomendado | |||
| Sistema de transmisión | Palanca de cambios | Perno de abrazadera de la palanca de cambios | 4-6 millas náuticas | Recomendado | No recomendado | No utilice compuestos antiadherentes ni fijadores de roscas líquidos en los tornillos relacionados con el sistema hidráulico del freno para evitar contaminar las líneas hidráulicas. |
| Perno de integración de la palanca de cambios | 4-6 millas náuticas | Recomendado | No recomendado | |||
| Perno de la tapa superior de la palanca de cambios (Shimano) | 4 MN | Recomendado | No recomendado | |||
| Desviador delantero | Perno de fijación del desviador delantero de montaje directo | 6-7 millas náuticas | Recomendado | No recomendado | ||
| Perno de abrazadera del desviador delantero | 5-7 millas náuticas | Recomendado | No recomendado | |||
| Perno de ajuste del cable del desviador delantero | 5-7 millas náuticas | Recomendado | No recomendado | |||
| Desviador trasero | Pivote del desviador trasero | 10-12 millas náuticas | Recomendado | No recomendado | ||
| Pivote del desviador trasero del sistema UDH | 25 millas náuticas | Recomendado | No recomendado | |||
| Perno de polea M4 | 3 MN | Considere con precaución | Considere con precaución | |||
| Perno de polea M5 | 4 MN | Considere con precaución | Considere con precaución | |||
| Perno de la tapa de bloqueo del desviador trasero M3 (Shimano) | 1,5 millas náuticas | No recomendado | No recomendado | |||
| Perno de ajuste del cable del desviador trasero | 5-7 millas náuticas | Recomendado | No recomendado | |||
| Juego de bielas | Perno de doble cara para plato | 6-8 millas náuticas | Considere con precaución | Considere con precaución | ||
| Perno de plato simple | 8 MN | Considere con precaución | Considere con precaución | |||
| Perno de brazo de manivela M5 (SRAM de 3 pernos) | 7 Millas Náuticas | Considere con precaución | Considere con precaución | |||
| Perno de brazo de manivela M4 (SRAM de 8 pernos) | 4-5 millas náuticas | Considere con precaución | Considere con precaución | |||
| Perno de fijación del brazo de la manivela M6 (Shimano) | 12-14 millas náuticas | Considere con precaución | Considere con precaución | |||
| Tapa del brazo de la manivela (Shimano) | 2-4 millas náuticas | No recomendado | No recomendado | |||
| Perno de fijación del brazo de la manivela (DUB) | 54 millas náuticas | Recomendado | No recomendado | |||
| Perno de fijación del brazo de la manivela (rotor) | 30-35 millas náuticas | Recomendado | No recomendado | |||
| Perno de fijación del brazo de la manivela (EE) | 52 millas náuticas | Recomendado | No recomendado | |||
| Perno de manivela cónico cuadrado M8 | 30 millas náuticas | Recomendado | No recomendado | |||
| Pedales | Eje del pedal | 25 millas náuticas | Recomendado | No recomendado | ||
| Perno de fijación de calas de carretera (3 pernos) | 6-8 millas náuticas | No recomendado | Recomendado | |||
| Perno de fijación de calas de MTB (2 pernos) | 8 MN | No recomendado | Recomendado | |||
