ITEM NAME:TL90 Digital Pitch Gauge LCD Backlight Display Blades Angle Measurement Tools 100% brand new and high quality Features: This TL90 gauge can be used on the helicopter that is equipped with stabilizer bar or flybarless, the built-in digital gyro can detect the height of the blade automatically and display on the backlight LCD screen. Automatically detect the horizontal angle. It has automatic screen inversion function. It can delay angle back to zero and lock it. Specifications: Applicable Length Of The Main Rotor: 250mm-800mm(9.84-31.50in) Applicable Width Of The Pulp: 20mm-75mm(0.79-2.95in) Operating Voltage: 3.0V DC Power Supply: 2 x CR2032 (NOT included); Operating Temperature: 0-40℃ï ¼Ë†32~104℉ï ¼â€° Precision Measurement: 0.1 degree Measuring Range:  ± 90 ° Body Size: app.108x22mm/4.25x0.87in Display Size: app.52x33mm/2.051.30in Note: No retail package Transition: 1cm=10mm=0.39inch Please allow 0-1cm error due to manual measurement, please make sure you do not mind before you.This TL90 gauge can be used on the helicopter that is equipped with stabilizer bar or flybarless, the built-in digital gyro can detect the height of the blade automatically and display on the backlight LCD screen.