Hirobo HI2521099 Tuning Collar 2 x 6 x 6 F7.3 x 0.5  [HI2521099]

Precision collar to tune axial play

This compact collar appears in Hirobo general parts under model HI2521099 with the size notation 2 x 6 x 6 F7.3 x 0.5. It is intended for use in hobby-grade helicopter assemblies where a short collar is necessary to position or retain rotating or sliding components on shafts.

Fit notes: listed as a Hirobo helicopter general part, the collar is compatible with Hirobo rotorcraft component sets and other small RC helicopter builds that take the same collar dimensions. Always measure the shaft diameter and neighbouring parts before fitting to avoid interference.

Tuning tips: collars of this type help reduce axial play and keep consistent spacing between moving parts, which can sharpen responsiveness. Fit incrementally and test rotor response after each adjustment to find the desired behaviour.