Hirobo HI2521057 Collar 4 x 6 x 3 RC helicopter collar part  [HI2521057]

Collar 4 x 6 x 3 overview

This Hirobo HI2521057 collar is an RC-scale accessory defined by the 4 x 6 x 3 sizing in its product name. It serves as a compact spacer component in model assemblies where that collar dimension is required. The description here keeps strictly to the provided naming and functional role without asserting unlisted specifications.

Installation is straightforward on compatible linkages or shafts that accept a 4 x 6 x 3 collar: slide the collar into place, verify fit and axial clearance, and secure the surrounding retaining elements as per the original assembly. If a set screw or retaining clip is part of your model's assembly, use it to lock rotational or axial movement; otherwise confirm fit by trial assembly and minimal movement checks.

In a tuning context this collar is used for spacing and alignment rather than performance enhancement. Adjusting collar placement affects stack height and endplay in small assemblies, so changes should be made incrementally and checked for binding or excess play during control surface and rotor checks.