The JR® digital pitch gauge is designed for helicopter pilots who want to measure any point of rotational along the root axis of a rotor blade easily. Its all metal frame is compact and lightweight so it can work with small blades used with 250-class helis, yet has a spring-loaded blade clamp that can open up to work with blades as wide as 75mm. Its electronics and gyroscopic sensor are accurate to within 0.1 degree and can detect pitch ranges of plus or minus 90 degrees. The large LCD display offers professional-level clarity and should you ever leave the unit sitting still for more than 20-minutes, it will shut itself off to conserve the replaceable battery.