Description

A fully engineered replacement trimmer head, for trimmers that use a 10mm x 1.25 LHF, 10mm x 1.25 LHM, 8mm x 1.25 LHM or 7mm x 1.0 LHM arbor.
Hammerhead Performance Trimmer Heads are the toughest trimmer heads on the planet.

With 4 different styles and 13 different models there is a Hammerhead Performance Trimmer Head that will fit 90% of all trimmers, the exclusion being trimmers with extended spindles or unique brand/model specific trimmer heads.
This model is a likely fit for straight shaft Echo, Redmax, Kawasaki, John Deere, Green Machine, Tanaka, TMC, Maruyama, Astron, Shindawa, Green Machine, Ryobi, Homelite, McCulloch, Brush King, Dolmar and others.
PLEASE MAKE SURE THIS MODEL WILL FIT YOUR TRIMMER BY USING OUR PART LOOKUP system.
TYPE 1 Model HH-MC425-10125 features:
Line advance button with a high-strength, cast and precision machined, aluminum alloy inset.
Quick Spool loading system for 22 second line loads.
Ultra Tough Nylon component construction with carbon fiber composite arbor assembly for rugged durability.
Works on STRAIGHT SHAFT trimmers only.
Fits receiving bolts sized to accept a 10 mm x 1.25 LHF, 10 mm x 1.25 LHM, 8 mm x 1.25 LHM or 7 mm x 1.0 LHM arbor.
Capacity: 19′ x .080 dia. 16′ x .095 13′ x .11 dia.
Outer diameter: 4.25″
Height: 3.25″
Weight: 14 oz
UPC: 860369000321
LIFETIME REPLACEMENT COVERAGE
All Hammerhead Performance Trimmer Heads have lifetime replacement coverage starting with our one year full warranty for manufacturers defects and continued through our lifetime low cost, part replacement program.

What makes Hammerhead Performance Trimmer Heads a tougher part than your original trimmer head (or other)?

• High-strength cast aluminum alloy protected bump knob ⋅ Critical protection where it counts.
• All nylon parts are not created equal ⋅ Typical OEM trimmer heads contain a nylon reinforced with glass fillers. In contrast, Hammerhead Performance Trimmer Heads use a high-grade, nylon. One strengthened with an elastic formula designed to distribute impact force. As a result, Hammerhead performance trimmer heads can withstand higher levels of impact stress, longer terms of abrasive wear 500 times beyond ISO shock test standards.
• A better fit—right out of the box ⋅ Hammerhead performance trimmer heads set a higher standard. When we make trimmer heads, each part measures within tenths of millimeters from each other — meaning a glove-like fit and no fiddling with stubborn parts.  No struggle to put together a trimmer head. With Hammerhead all parts slide together smoothly ever single time.
• A wobble free arbor ⋅ Hammerhead performance trimmer heads bolt to a billet aluminum center arbor contained within a carbon fiber assembly. A better way to attach a trimmer head. While all other trimmer heads provide a universal “bag of bolts” and ask you to pick out one that fits okay. Hammerhead has a large center arbor that is friction fitted and balance checked at the factory for an accurate and smooth spin. One specifically sized to your trimmer’s receiving bolt.
• Superior debris protection ⋅ Trimmer heads fail when dirt and grit get inside. Debris that will quickly wear the moving parts that advance the line. Hammerhead’s large, overlapping interior walls interlock and block foreign matter from entering critical mechanisms.