Sumner 780435 Rotary Earth Clamp

Attaches and detaches in seconds.
Positive anti-arc bearings take loads up to 400 amps.
Makes up earth leads three ways - lug, clamp-on and bare cable.
Rotary head turns with the pipe - puts an end to earth lead twist.
Provides quick, positive earth for roll-out welding of pipes and fittings - eliminates weld pinholes caused by poor earthing.