Hirobo HI2539023 M3 x 4 Hex Button Screw for RC Helicopter Assemblies  [HI2539023]

Compact Hex Button Bolt Specification

This hexagon button bolt is listed as Hirobo HI2539023 and is intended for general-purpose fastening tasks in RC helicopter assemblies. The M3 x 4 label identifies the thread size and length commonly used for securing small structural and accessory parts.

For reliable installation, use an appropriate hex driver and avoid over-torquing to prevent stripping. The bolt's low-profile head is helpful where reduced clearance is required and supports routine tuning and maintenance tasks.

Check that the receiving part accepts M3 x 4 fasteners and that sufficient thread engagement exists before final tightening to ensure durable service in your model.