Hirobo HI0304161 EMBLA EB Main Mast Lock — main mast lock for EMBLA EB model helicopters  [HI0304161]

Main mast lock for EMBLA EB

This is an RC-scale main mast lock designed for the EMBLA EB series, supplied as HIROBO part number HI0304161. It serves as the retention component that secures the main mast to the rotor assembly on EMBLA EB model helicopters, intended for hobby-grade model use only.

In practical terms the lock is used during routine servicing and preflight checks to hold the main mast in position while you inspect the rotor head, replace bearings, or perform alignment work. The part is intended as a direct replacement item where original lock wear or play affects mast positioning.

Installation is typically done during rotor head removal or reassembly, where the lock interfaces with the main mast seating and retention points; it plays a role in setup and tuning by keeping the mast stable while you adjust swash geometry, check tracking, or balance rotor components.