Features: 1.Show both engine rpm and hours of operation 2.Work on 2 or 4 stroke gas powered engine, induction type design, only need to connect the cable on the spark plug can operate 3.LCD screen display showing data clearly 4.Programmable maintenance interval setting 5.Build in battery for long time use Specification: Features: Show both engine rpm and hours of operation. Work on 2 or 4 stroke gas powered engine, induction type design, only need to connect the cable on the spark plug can operate. LCD screen display showing data clearly. Programmable maintenance interval setting. Build in battery for long time use. Specifications: Material: Plastic Color: Black Hours Range: 99999H Hours Accuracy: 0.1H RPM Range: 300~30000rpm RPM Accuracy: 10 rpm Waterproof Rate: IP65 Battery: CR2450 (not included) Item Size: approx. 7.4 x 4.7 x 2cm / 2.9 x 1.8 x 0.8inch Package Weight: approx. 65g/2.3oz Package Included: 1 x Tach/Hour Meter with Wire 2 x Self-locking Nylon Zip Cable Tie Note: It is easy to install, but professional installation is highly recommended. PackageList: