(2-Pack) 3.7V 150mAh CW-SHBA300HPC Battery Compatible with Sennheiser BA300 Headphone, Set840-S/TV Set900 Set830/S/TV RR840/S RS4200 RI830/S RI900 RR4200 HDI830 IS410 RI410 Rechargeable

Compatible With Sennheiser BA300 RI830 RI830-S RI900 RR4200 HDI830 IS410 RI410 Set840-S Set840-TV Set900 Set830 Set830-S Set830-TV RR840 RR840-S RS4200 Headphones Receiver
Replacement for the Following Battery Model/Part Numbers: BA300, BA 300, BA-300, Cpp-523, HC-BA300, NCI-PLS100H, SENBA-300, 302716, 500898.
Compatible with the Following Sennheiser IR and RF Wireless TV Headphones Models: IS410, IS410TV, IS410-TV, RI 410, RI 830, RI 830-S, RI 900, RR4200, RS4200, RS4200TV, RS4200TV-2, SET 830, SET 830-S, SET 830-TV, SET 840, SET 840-S, SET 840-TV, SET 900.
3.7V 140mAh 0.5Wh Lithium-Polymer Rechargeable Battery Pack.
Package Included: 2 x Batteries