Hirobo HI2521145 Collar 2 x 3 x 6 small collar for helicopter general parts  [HI2521145]

Small collar for helicopter assemblies

This HIROBO collar is an RC-scale helicopter general part intended as a simple retention and spacing element within rotor and control link assemblies. Its compact 2 x 3 x 6 marking indicates the nominal collar dimension used to locate components on shafts or within small housings.

Use this collar where precise axial positioning is needed to limit endplay or to create a reliable bearing surface for adjacent parts. Inspect mating shafts and bores for burrs before fitting and verify the collar seats squarely to avoid eccentric loading that can affect rotor balance.

In tuning and setup, collars like this serve a subtle role: consistent spacing helps maintain predictable geometry for linkages and rotor pitch components, reducing the need for repeated shims or adjustments during trim and testing.