Hirobo HI2521143 Collar 2 x 3.5 x 3 RC helicopter general collar  [HI2521143]

Replacement collar for RC helicopters

This Hirobo collar is an RC-scale general replacement part listed as HI2521143, intended for use in helicopter assemblies where a small collar is required to locate or retain shafts and linkages. The product name carries its nominal size, which helps match it to shafts or components that call for a 2 x 3.5 x 3 collar.

Installation is straightforward: position the collar on the shaft at the required location, verify alignment with mating parts, then secure with the appropriate set screw or compatible fastener specified by your model's parts list. Confirm fit and clearance before flight to avoid binding.

In tuning and setup, collars like this serve to lock precise positions on control linkages or rotor components, allowing repeatable adjustments during trim work and maintenance. Keep spare collars on hand for quick replacement during bench tuning or field repairs.