2 x 3.5 x 3 Collar for RC Helicopter Shafts - Hirobo HI2521143  [HI2521143]

Helicopter collar — general replacement

This Hirobo collar, listed as HI2521143, is a general-purpose replacement part for small helicopter assemblies where precise shaft location or retention is needed. Its marked size, 2 x 3.5 x 3, simplifies matching the part to your model's requirements.

To fit, slide the collar into position on the shaft, check engagement with surrounding components, then secure with the correct set screw or other fastener called out in your model documentation. Test that linkages move freely after fitting to prevent interference during operation.

Collars are useful during setup to lock linkage geometry for repeatable trim sessions and straightforward maintenance. Carry extras for fast field repairs and trimming adjustments.