2 x 4 x 12 Collar HI2521131 for Hirobo RC Helicopter Parts  [HI2521131]

Small retention collar for helicopter shafts

This Hirobo collar is a compact RC-scale component intended for use in helicopter general parts where small axial retention is required. The part is identified as HI2521131 and referenced by the 2 x 4 x 12 marking; it serves to locate and hold components on short shafts in model rotor systems.

Fitting is direct: slide the collar to the required axial position, line up adjoining parts, then secure with the model's prescribed hardware. Clean the shaft and collar seating surfaces prior to assembly to avoid misalignment or unwanted play.

As part of routine maintenance the collar provides a simple stop to maintain alignment of blade grips, gears, or spacers. If you observe end play or increased vibration, inspect the collar seating and clamping for wear or slippage.