• Professional diagnostic tool to prove/disprove spark at individual cylinder
• First step in diagnosing non-firing vehicles, motorcyles and small engines
• No more guessing--receive clear visual signal when spark is present
• Quickly and easily attaches between spark plug and wire with universal plug/wire connectors
• Rugged polycarbonate housing with replaceable bulb; stainless steel plug adapter

When a vehicle, motorcycle or small engine turns over but won't start you need to begin a process of elimination for the cause. The first test to perform (okay--maybe the second after checking the fuel gauge) is whether or not spark is reaching the cylinder. Shade-tree mechanics often unplug the wire trying to see if spark jumps to any metal object, but if you've ever had an ignition spark go through your finger you know how painful that method can be. This simple but effective device gives an unmistakeable (and painless) signal when spark is present so you know where to look next. Durable polycarbonate construction with stainless steel plug adapter, easy-flex rubber wire adapter. One-year warranty.