Hirobo HI2521146 Compact Collar 7 x 8 x 4 for RC Helicopters  [HI2521146]

Helicopter shaft retention collar

This Hirobo HI2521146 collar is a compact retention component sized 7 x 8 x 4, built to hold shafts, linkages, and sliding parts securely inside RC helicopters and similar model assemblies.

Designed as a straightforward replacement, the collar offers axial positioning rather than primary load support. In use it helps prevent cyclic linkages, tail shafts, and intermediate studs from shifting under vibration or during setup and tuning. Verify the collar's 7 x 8 x 4 dimension matches your shaft diameter and bore before fitting.

Installation notes: clean mating surfaces to remove burrs or debris, slide the collar into position and confirm axial seating and free rotation where required, inspect regularly for wear and replace if the fit loosens. The part is supplied as a routine maintenance and tuning accessory for RC helicopters.