This hop up unit is manufactured from dural EN AW 7075 alloy giving it steel-like strength and the light weight of aluminium. Developed through extensive testing it is precisely made for optimum feeding and performance.

The innovative collet nut locks onto the inner barrel once installed forming a very tight air seal. When installed with the Retro Arms CNC gearbox they can be screwed together to keep the whole system aligned and prevent air leaks.

Installation notes:
- use ethanol to lubricate the outside of the bucking
- use a small dab of grease to hold the nub in place (warning: do not allow oil or grease to contaminate the inside of the bucking)