Hirobo HI2507002 E-ring Retaining Clip for M4.0 Shaft 10pcs  [HI2507002]

Small retaining clip for model shafts

The Hirobo E-ring is designed to fit M4.0 shaft grooves and is supplied as a set of ten for maintenance and part swaps. It serves as a straightforward axial stop to hold gears, bearings or linkages in position on shafts used in model helicopters and other hobby projects.

Installation is straightforward: press the ring into the groove until it seats and secures axial components. Check the shaft groove for debris or burrs before fitting and make sure the ring fully engages the groove to prevent slippage during use. This helps maintain consistent axial placement so drivetrain alignment and bearing preload stay correct.

These rings are inexpensive service parts intended for periodic replacement when overhauling drive assemblies. Carry spare clips when servicing small drivetrains, linkage stacks, or any build that relies on a groove-mounted retaining clip.