Autoview Canbus Adapter Universal Slim Key Drill Presses Gearless Palm Ratchet Gearless palm Size:Off Set Ring Spanner 1 2 x 7 16in Gearless Palm Ratchet Gearless palm ratchet 1 4 square drive for use with sockets and accessories 1 4 hexagon drive for use with screwdriver bits and accessories Handle designed for easy rotation with the fingers Use with an extension bar to create a ratcheting T bar Gearless mechanism for use in confined spaces Twist reverse for quickly and easily changing between tightening and loosening Specifications Dimension 4 x 19mm metric 12VDC ignition output with max current of 1 It can recognize car protocol and consequently to choose the right synchronization to the car