Tool Aid SG 23500 Back Probe Kit Color identified Back Probes for use on harness connectors, fuel injectors and automotive sensors Stainless steel, straight, 45 and 90 degree probes in .027" and .040" diameters Insulated body for testing up to 30 volts 12" extension leads quickly plug in to permit testing in recessed areas, compatible with standard 4mm plug Probes easily insert into automotive connectors