The single piece hub is made from forged or solid aerospace aluminum alloy. After machining, the outside is shot-peened and thereafter the hub is anodized as corrosion protection (the hub's outside is additionally painted for sea applications). The blade bearings are special design ball bearings, where the balls act as split retainers for holding the blades in the hub, which creates an increased safety factor against blade loss.
The outer bearing race is a single piece part and pressed into the hub, while the inner race is split and installed on the blade ferrule. The blade preload is adjusted by changing the thickness of a plastic shim. Blade and bearing are secured in the hub by a retention ring.

The pitch change of the blade is enabled by an excenter pin installed in the blade ferrule. A plastic block made out of special carbon material connects the pitch change pin with the piston and the axial movement of the servo piston turns the blades.
A return spring and a sleeve, which acts either as the high or low* pitch stop, are installed between the piston and the front plate as the oil pressure counterpart and completes the single acting pitch change system .

Two check nuts located outside the hub adjust the low or high* pitch stop. The inner part of the hub shank is used as a cylinder for the pressure oil supplied by the propeller governor. This arrangement allows a simple and light-weight design without any additional parts. All weights required for static propeller balancing are installed on the front spinner bulkhead.

(* = counterweighted models)
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