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

Precision shaft collar for RC helicopters

The Hirobo HI2521146 collar, measured at 7 x 8 x 4, acts as a compact axial clamp to secure shafts, linkages, and sliding components inside RC helicopters and related model assemblies.

Offered as a direct replacement, the component focuses on maintaining axial position rather than carrying primary loads. In practice it prevents cyclic linkages, tail shafts, and intermediate studs from shifting with vibration or during adjustment. Always confirm the 7 x 8 x 4 specification fits your shaft and bore before installation.

Fitment guidance: clean mating faces, slide the collar into the required position and ensure proper axial seating while allowing necessary rotation, inspect periodically for wear and exchange it if the fit loosens. This collar is intended as a straightforward maintenance spare for RC helicopters.