This is the Helicopter Pitch Gauge from HeliMax. FEATURES: Allows easy setting of pitch for main blades and flybar paddles Works with a variety of main rotor blade sizes from 425mm to 710mm chord blades commonly found on 250 to .90 size helicopters Measures pitch from -15 to +15° INCLUDES: Helicopter Pitch Gauge jxs 04/29/10 updt lmm 6.4.10 ir/jxs