Micro Retaining Collar 5 x 7 x 2 for RC Models Hirobo HI2521137  [HI2521137]

Micro shaft collar for helicopters and models

The Hirobo HI2521137 collar, sized 5 x 7 x 2, is made for use in model helicopters and other compact scale assemblies where an axial clamp is required. It functions as a compact retainer to keep shafts, spacers, or bearings located within constrained mechanical stacks.

Fitting the collar is simple: place it at the required axial point on the shaft, ensure it lines up with adjacent components, and secure it according to your model's fastening method. It is intended for axial retention and minor clearance adjustment rather than for bearing heavy torque, so inspect fit and rotation before final tightening.

During routine maintenance you can use the collar to tweak axial endplay or to lock components after shimming. As this is an accessory sized for model systems, always confirm compatibility with your shaft diameter and clearance to avoid interference with rotating parts or bearings.