This kit includes a continuity tester, spark plug tester, 6 & 12 volt auto circuit tester and a 90-600 volt tester light.   Features:     Continuity tester Checks for short circuits and faulty appliances Self powered Complete with full 3-FT ground clip wire    Spark plug tester & handy pocket screwdriver Pocket screwdriver Instantly tells whether or not spark plugs are firing Quickly find dead spark plugs    6 & 12 volt auto circuit tester Checks complete accessory circuits For use on Marine, Auto and Trailer Quickly finds Faulty taillights, Head Lights, Turn Signals Fuses, Sockets, Connections, and short circuits     90-600 volt tester light Instantly tests Fuses, Outlets, Extension cords, Switches, Ect. For 110 Volts & 220 Volts.