Hirobo HI2521095 Collar for Helicopter General Parts 3 x 5 x 4.5F  [HI2521095]

Durable Collar for Shaft Retention 3 x 5 x 4.5F

This collar is supplied as an RC-scale accessory for helicopter general parts and assemblies. Identified by model HI2521095, the 3 x 5 x 4.5F marking is the size reference you should use to check fit with the mating shaft, pin, or bore.

As a locating and retention element in rotor or transmission subassemblies, the collar helps keep small shafts and linkages in position. When fitting, align the 3 x 5 x 4.5F dimension to the component, confirm correct orientation, and make sure the collar sits firmly to avoid displacement under load. Proper fit contributes to consistent trim behavior.

For service inspections look for wear, out-of-round condition, or looseness at the interface with shafts or bearings. If the collar no longer provides firm retention replace it. Maintain clean mating surfaces so the collar continues to deliver repeatable performance during maintenance cycles.