HDE Professional Digital Infrared Photo Tachometer RPM Motor Speed Gauge Tach Ultra durable and portable design make it easy to transport and use anywhere Extra-large, 5-digit LCD display with high accuracy of +/- 0.05% | Auto zero adjustment Powered by 1 x 9V Battery (not included) Stores last, minimum, and maximum readings and can be displayed at any time. Package Contents: 1 x Digital Photo Tachometer, 1 x Carrying Case