SP Tools Adjustable Advance Timing Light SP62040Quickly tune up cars, trucks, marine and recreational vehicles Works on conventional, electronic and computer controlled ignition systems on both adjustable and nonadjustable timing systems Patented Skip circuitry Tests up to 10,000RPM Dial type timing advance (0 60 score) Heat resistant metal inductive pick up One handed operation Detachable leads for easy replacement and use Protective hand guard for added safety Rotating barrel for better aim at