Adjustable double hole car spark plug tester detector Ignition Plug Analyzer Diagnostic Tool. Place the Spark Plug into tester hole 1 or 2; If you want to compare the new spark plug and old one, place new spark plug into hole 1 and the old on into hole 2.

Accessories: 1pc x Spark plug tester 1pc x Power Adapter
Brand: OBDResource
Model: ST100
Type: Spark Plug Tester
Vehicle Type: Passenger Vehicle
Volt: 12 Volt
Warranty: Lifetime