PLEASE NOTE I WILL BE SUPPLING THIS WITH A 501 BULB NOT A 921 SHOWN IN THE PICTURE DUE TO VARYING BULB HOLDER ISSUES 1x 12v Back Probe Test Light Lamp Kit With Probes Automotive. Purchasing from me your are supporting fellow technicians. These are a must have tool for me in diag work. These units are hand made good quality, made with high flex heat resilient wire Supplied with 2x back probes a useful lamp fitted with 4mm banana stackable plugs, made for probing into the back of automotive multi plugs complete in a neat 3D printed housing with cable clips Make testing easier there’s no need to find a good ground to clamp to when you can just probe into both power and ground wires and check integrity of both Makes bridging circuits for testing easier and safer, the incandescent bulb will avoid short circuiting Can be used with 501LED if preferred Colours maybe random Want a certain colour? Ask me I can supply in most colours