Shure SB900B, Li-Ion Battery, 3.7 V / 1320 mAh, Lifetime for ULX-D 1 mW and 10 mW up to 8.5 h, Otherwise approx. 30% more than AA batteries@+@+*Suitable for:*@+@+, All PSM300 (only P3RA, not P3R), PSM900 (only P9RA and P9RA+, not P9R), PSM1000, SLX, FP, QLX-D, ULX-D, Axient Digital (AD1 and AD2 only, not ADX1 and ADX2)