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Estry

Estry replacement battery 800mAh 3.7V for Sena GT-Air II Neotec II J-Cruise II SRL-01 SP51 PTC802050

SKU CH-R7WY-6CKPC

Replacement lithium battery delivers 800 mAh at 3.7 V for Sena GT-Air II, Neotec II, J-Cruise II and SRL-01 headsets

  • TypeBatteries
  • Battery Pack1-pack
  • Battery TypeLithium
  • Battery Capacity800mAh
  • Battery Voltage3.7
  • 800 mAh capacity keeps your headset running longer
  • 7 V lithium chemistry matches the original power spec
  • built-in overcharge and short-circuit protection extends safe use
  • 0 x 20.0 x 8.0 mm size fits GT-Air II Neotec II J-Cruise II SRL-01
  • certified to ISO9001 RoHS CE UN38.3 MSDS standards

Direct replacement for Sena helmet communicators

This Estry battery matches the original SP51 specifications with a 3.7V 800mAh lithium cell. It fits the GT-Air II, Neotec II, J-Cruise II and SRL-01 communicators. The pack contains one 52.0 x 20.0 x 8.0mm unit weighing 40.0g. It delivers 2.96Wh and carries ISO9001, RoHS, CE, UN38.3 and MSDS certifications.

Riders needing a fresh power cell for the listed

The battery is built to the exact dimensions and voltage of the factory part, so installation is straightforward. Buyers who need a different voltage, a higher capacity or a multi-cell pack should look at other options. Anyone using a communicator not named in the compatibility list must verify fitment before ordering.

800mAh 3.7V lithium cell in SP51 form factor

Capacity and voltage are the decisive figures for this replacement. The 800mAh rating at 3.7V provides the same energy budget as the original battery. If your device requires a different capacity or voltage, this cell will not be suitable.

Highlights

  • 800 mAh capacity keeps your headset running longer
  • 7 V lithium chemistry matches the original power spec
  • built-in overcharge and short-circuit protection extends safe use
  • 0 x 20.0 x 8.0 mm size fits GT-Air II Neotec II J-Cruise II SRL-01
  • certified to ISO9001 RoHS CE UN38.3 MSDS standards

Specifications

BrandSena
TypeBatteries
Battery Pack1-pack
Battery TypeLithium
Battery Capacity800mAh
Battery Voltage3.7

Questions about this item

What are the exact dimensions of the Estry 800mAh 3.7V battery for Sena GT-Air II and SHOEI Neotec II?

The battery measures 52.0 x 20.0 x 8.0mm and weighs 40.0g, matching the original PTC802050 form factor for the SRL-01 (SP51) communication module cavity.

How is the Estry replacement battery installed in the Sena SRL-01 (SP51) unit, and what step is commonly missed?

Remove the SRL-01 module from the helmet, open the battery compartment cover, disconnect the old pack, connect the new 3.7V 800mAh lithium battery ensuring correct polarity, then reseal the cover before remounting the module.

What ongoing maintenance does the Estry 800mAh lithium battery require for Sena GT-Air II and J-Cruise II headsets?

Store at partial charge if unused for weeks, avoid full discharge, recharge every few months during off-season, and replace when operating time drops significantly below the rated 2.96Wh capacity.

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