Hirobo HI2521092 Collar 5 x 13 x 16 Shaft Spacer for Helicopters  [HI2521092]

Precision Collar for Rotor Assemblies

This collar is made as an RC-scale accessory for use with Hirobo helicopter components. The marking 5 x 13 x 16 denotes the bore, outer diameter, and thickness so you can check fit and clearance before installation.

Installation is simple for experienced model technicians: the collar serves as a spacer or locator between rotating parts and fixed housings, helping to keep axial position and uniform clearance. Always confirm shaft diameter and internal bore match to avoid forcing the part into place.

During setup and routine tuning the collar lets you make small axial adjustments that influence rotor balance and linkage geometry; swapping collars or adding shims of equivalent dimensions is a practical method to fine-tune alignment without altering primary components.