Johnson AS888 Automatic Float Switch For use with 12V & 24V Pumps Max Amp : 15A For fully automatic bilge pumping operation, connect the AS888 Automatic Switch to your bilge pump. The Switch has a time-proven micro switch without mercury. When water exceeds the acceptable level, the pump is turned on by a rolling steel ball, which changes the pressure on the micro switch. The AS888 attaches to any SPX FLOW Johnson Pump bilge pump through the clip on ”T-slot” Can be used with 12, 24 or 32V systems