Don't wait too long to rebuild your motor - but don't do it too soon either. 

This easy-to-use tester checks ring seals, valves, even head gaskets.

• Much more accurate than traditional testers - Reads critical leakdown to .5% (1/2 of 1%)
• Gauges have back lights for easy readability and low battery indicators
• 14 mm spark plug connector and hose included
• Control inlet valve avoids shock to gauges when air is turned on, allowing more accurate readings, easier use and longer gauge life
• Rugged design features rubber bumpers to protect gauges
• Silver carrying case included