S-8770 is the replacement battery for SONY NP-F770, compatible with SONY HVR-V1/Z1/Z7, DSR-PD190, HD1000E, etc. S-8770 can exchange digital info with the cameras, and display remaining power info on the camera viewfinder. With 7.2V nominal voltage, the S-8770 has 31Wh / 4.4Ah capacity, and can run approx 3.5 hours on SONY HVR-Z1 camcorder when LCDmonitor is on. The S-8770 can be charged on SWIT Dual channel charger S-3602F and SONY original charger. It takes about 2 hours and 50 minutes to charge from empty to 100%.