Hirobo HI2521114 Collar 3 x 7 x 17.5 for RC helicopter general parts  [HI2521114]

This Hirobo collar is an RC-scale replacement part intended for use in helicopter general parts assemblies. The naming indicates a 3 x 7 x 17.5 dimensional form factor commonly used where precise axial location of shafts or small components is required. The piece serves as a mechanical spacer and retention element rather than an active component.

Installation is straightforward on typical helicopter linkages and rotor assemblies: slide the collar onto the shaft to set axial position, confirm fit against adjacent bearings or hubs, and secure with any existing set screws or retention hardware already present in the model. Ensure mating surfaces are clean and that the collar clears nearby moving parts before flight.

Tuning role: use this collar to fine-tune axial spacing when adjusting blade tracking, tail pitch link geometry, or gearbox engagement in model helicopters. Small changes in collar placement can affect alignment and end-play, so make incremental adjustments and verify movement under static and low-speed rotation before full operation.

Packing

• Item supplied as individual collar, sold per piece.