Grass Gator 4680 Brush Cutter Head with Metal Blades | Extra Heavy Duty Replacement for Straight Shaft Gas Trimmers 25cc+ | Commercial Grade Universal Fit

What It Is

The Grass Gator 4680 is a commercial-grade brush cutter head that replaces standard trimmer heads on straight-shaft gas trimmers (25cc+). It uses three metal blades to cut thick weeds, brush, and heavy grass where nylon line would fail.

Fitment & Compatibility

• Shaft type: Straight shaft only. Does not work on curved-shaft trimmers.
• Engine size: Requires 25cc or larger. Smaller engines lack torque and may stall or damage the gearbox.
• Attachment system: Universal fit – uses a standard 10mm (3/8″) hex shaft and a retaining nut (M10x1.25 LH thread). Most straight-shaft trimmers from Echo, Stihl, Husqvarna, Ryobi, and Craftsman use this pattern. Confirm your trimmer’s shaft end has a hex cutout and uses a left-hand thread nut.
• Spindle size: The head fits spindles with a 25.4mm (1″) diameter. Measure your trimmer’s output shaft before buying.
• No OEM-specific adapters needed – it mounts directly without extra parts.

Key Things to Know

• Installation difficulty: Moderate. You must remove the old head and may need a tool to hold the shaft still. A locking pin or block of wood works. The left-hand thread can be confusing – turn clockwise to loosen, counter-clockwise to tighten.
• Metal blades are sharp and dangerous. The head throws debris up to 50 feet. Always wear eye protection, long pants, and boots. Never use near rocks or fences – blades can shatter.
• Not for string trimming. The metal blades will damage grass, flower beds, and soft landscaping. Use only for brush, briars, saplings up to 1″ thick, and overgrown areas.
• Blade replacement: Blades are sold separately (Grass Gator 4680-3 pack). They dull quickly on sandy soil – expect to replace after 3–5 hours of heavy use. Keep spares on hand.

Should You Buy It

Buy this if you regularly clear heavy brush, blackberries, or small saplings and have a 25cc+ straight-shaft trimmer. It’s a durable, affordable upgrade from string heads for rough work. Skip it if you only trim lawn edges or have a curved-shaft trimmer – it won’t fit or work well.