Milikaco Replacement Gear Head for FS-Series String Trimmers — 1in Square Shaft, 10‑Tooth Aluminum Gearbox

The Milikaco replacement gear head is a direct-fit aluminum gearbox assembly designed to restore power and reliability to compatible FS-series string trimmers.

If your brush cutter or string trimmer has a worn or broken gearbox, this Milikaco replacement gear head provides a budget-friendly way to get back to cutting without buying a whole unit. The kit includes the gearbox, rider plate, thrust parts, collar nuts, and extra fixing screws so you can reassemble and return the head to service quickly. It’s engineered with a 10-tooth square shaft interface (25.4 mm / 1") to match many popular FS models; confirm compatibility with your model before ordering.

Will this gear head fit my FS-series trimmer?

Compatibility hinges on the gearbox interface and the operating rod diameter. This Milikaco unit is built for a square shaft of 1" (25.4 mm) and fits a long list of FS models; double-check the model number stamped on your current gear head or in the owner’s manual to be sure.

• Fits many FS models including FS55, FS80, FS85, FS90, FS111, FS120, FS130, FS240, FS250 and variants.
• Specification: 10 teeth gearbox with a square 25.4 mm (1") shaft.
• Confirm match visually or by measuring the operating rod before purchase.

What parts are included and what tools will I need to install it?

The replacement arrives as a small parts kit so you can rebuild the trimmer head without sourcing additional hardware. Milikaco supplies the main gearbox plus rider plate, thrust washer and plate, two collar nuts, and multiple fixing screws including seven extra stainless screws for reliability.

• Included: gear box, rider plate, thrust washer, thrust plate, 2 collar nuts, and fixing screws.
• Extra screws provided to replace stripped or broken fasteners during installation.
• Typical installation requires basic hand tools: sockets or wrenches, screwdrivers, and possibly a torque wrench for proper tightening.

How does Milikaco’s gearbox compare in durability and performance?

Milikaco uses low-pressure cast aluminum for a balance of lightness and mechanical strength, producing a compact, corrosion-resistant housing. The included metal screws and reinforced components aim to improve longevity versus cheap plastic replacements, though wear still depends on usage and maintenance.

• Aluminum casting reduces weight while maintaining structural integrity.
• Metal fasteners are included to improve assembly durability.
• Designed to replicate OEM fit and function as a cost-effective replacement part.

Who is this for? This Milikaco gear head is for homeowners, landscapers, and maintenance pros who need an affordable, OEM-compatible gearbox to repair FS-series string trimmers. It's ideal if you can confirm a 1" square shaft interface and want a durable aftermarket kit that includes extra screws and the parts needed to rebuild the head. If you prefer factory-original parts, compare your model’s part number; otherwise this Milikaco unit is a practical replacement for extending the life of a worn trimmer.