Hirobo HI2521013 Shaft Collar 3 x 8 x 9.5S Service Part  [HI2521013]

Compact collar for linkages and shafts

This collar is an RC replacement component recorded under Hirobo helicopter general parts. The 3 x 8 x 9.5S marking identifies the nominal size intended to match common shaft and linkage tolerances on small to medium RC helicopters, functioning as a compact spacer that locates rotating or sliding parts.

Install it when maintaining tail or main rotor linkages, shaft couplers, or other collared connections where accurate axial positioning is required. Installation generally means sliding the collar onto the shaft and securing it as per the original assembly; follow the helicopter kit's guidance for retaining parts and torque values.

Since this is a straightforward, low-cost spare, check bore fit and runout prior to reassembly and keep extras on hand for routine care and pre-flight inspections.