Spare batteries for anymember of the Z-Vibe or Z-Grabber series. Please note: these are special batteries not availablein stores. Please note : to turn the unit on, twist the switch tip in *just* until it starts to vibrate. Any further will not increase the vibration, but significant over-tightening (although hard to do), may damage the motor. Caution: contains small parts that may pose a choking hazard. Please handle with care.