It takes 8-12 hours to charge the battery initially, after which it can be charged in 6-8 hours.

This BA151 battery will work with the following Sennheiser wireless headphone models: IS 150, IS 300, Set 810, Set 250, Set 50, IS 380, Set 820, Set 2500, RS 4, RS 6, RS 8, RS 400, RS 30, RS 40, RS 45, RS 60, RS 65, RS 80, RS 85, RS 2400, HDI 302, and A 200.