RC Helicopter Collar 4 x 6 x 3 Hirobo HI2521057  [HI2521057]

Collar function and fit

This Hirobo HI2521057 collar is defined by the 4 x 6 x 3 measurement in its name and serves as a small spacer in constructions that require that specific collar size. The description remains focused on the named dimension and the collar's role in spacing and alignment.

Fitting involves sliding the collar onto a shaft or linkage that accepts the 4 x 6 x 3 size, verifying axial clearance, and locking it using the model's provided method. Use any set screw or retaining clip your assembly calls for, and carry out a trial run to ensure no unwanted movement occurs.

As a setup item, the collar affects stack height and endplay rather than delivering a performance upgrade. Make measured changes to collar position and inspect the assembly for binding or excess play during control and rotor checks.