Hirobo HI2521137 5 x 7 x 2 Shaft Collar for RC Helicopter Assemblies  [HI2521137]

Compact shaft collar for model use

This Hirobo HI2521137 collar measures 5 x 7 x 2 and is intended for model helicopters and other scale assemblies where a compact axial clamp is required. It acts as a simple retaining element to locate shafts, spacers, or bearings inside tight mechanical stacks.

Fitting is straightforward: slide the collar to the chosen axial position, align it with adjacent components, and secure using your model's existing fastener method. Its role is mechanical retention and micro-adjustment of axial clearance rather than serving as a high-torque load-bearing component, so check fit and rotational freedom before final assembly.

During tuning and maintenance, use the collar to refine axial endplay or to lock components after shim adjustments. Because this is sized for model-scale systems, confirm shaft diameter compatibility and ensure there is adequate surrounding clearance to avoid interference with rotating parts or bearings.