Hangar 9's new Micro Digital Tachometer is engineered using the latest technology. This handy tuning tool can measure the rpm of any engine equipped with a 2-, 3-, or 4-balded propeller. RPM is displayed in up to four digits, with a range of up to 32,000 rpm. A long lasting 3V 220mAh lithium battery is included. The Micro Digital Tachometers's auto shut-off feature prolongs batttery life, and a low-battery icon indicates when the battery needs to be changed. It's also small enough to easily fit into your pocket.

• Press the "Power" button to select the number of blades: 2-, 3-, or 4-blade.
• From a distance of 6-18 inches, aim the sensor at the spinning propeller of the airplane
• Be sure that the source of the light is from the sunlight. If it comes from a fluorescent lamp, the number showing on the LCD screen will be incorrect.
• To calculate rpm, simply multiply the number shown on the screen by 10.
• The safest positiion for using the tachometer is from behind the rotating propeller.