Hirobo HI2521075 3 x 7 x 7 Collar for Hirobo Helicopters  [HI2521075]

Overview of the shaft collar

This collar appears in the list of general Hirobo helicopter parts and functions as a compact shaft collar for positioning and retention duties on scale rotorcraft models. The numeric 3 x 7 x 7 designation simply describes the collar dimensions to guide fitment decisions, not extra proprietary features.

Used correctly the collar helps hold axial position of shafts and linkage runs during initial setup and while fine tuning. Installers usually rely on the model's original fastening approach, and should confirm there is no unwanted axial play or interference before completing the installation.

As a maintenance and tuning aid the collar can be employed as a spacer or stop to aid blade pitch consistency, swashplate indexing, and repeatable rotor settings when combined with the helicopter's native hardware. Regular checks for cleanliness and wear will help avoid inconsistent behaviour in flight.