This is the Limited Edition OS 55HZ-R DRS Ringed Helicopter Engine with the DRS (Demand Regulator System).

FEATURES:

DRS system delivers fuel to the regulator under constant pressure for precise fuel delivery throughout the entire tank from full to empty Mounting position of DRS is perfectly in line with the carb for consistent operation in all attitudes of flight Same mounting bolt pattern as the OS 50SX-H Hyper Dual needle 40L-R carburetor allows independent adjustment of idling, hovering and high speed with four arm throttle lever for use with a variety of servo brands HZ Hyper low profile six fin cylinder head Two year limited warranty through Hobby Services beginning at the date of purchase

INCLUDES: OS 55HZ-R DRS Ringed Helicopter Engine

REQUIRES: 10% to 30% nitro Fuel with at least 18% lubricant (Helicopter Mix) Starting equipment

SPECS:

Engine; Displacement: 0.55 cu in (8.93cc)

Bore: 0.91" (23mm)

Stroke: 0.85" (23.5mm)

Practical RPM: 2,000-20,000 RPM

Weight: 15.1oz (429g)