Hirobo HI2521124 Collar 12 x 15.9 x 6.8  [HI2521124]

Helicopter collar for shaft spacing

This is an RC-scale collar intended for helicopter general parts, listed as HI2521124 by Hirobo. The collar's nominal dimensions 12 x 15.9 x 6.8 are provided as the defining technical detail to match shafts and housings in helicopter assemblies.

Functionally, the collar serves as an axial spacer and positional locator within rotor heads and transmission stacks. It helps maintain concentricity and reduces axial play when installed as part of the original assembly layout.

Installation notes: fit the collar to the shaft and verify seating against adjacent components, inspect for wear or ovality before reuse, and follow the helicopter's original assembly practice to secure the collar in place.