Gear Heads · SKU B0GC6ZFC9L

4180 640 0114 Trimmer Gear Head and 9" x 20T Chainsaw Tooth Brush Cutter Blade

Name: 4180 640 0114 Trimmer Gear Head and 9" x 20T Chainsaw Tooth Brush Cutter Blade
Brand: YUTACOREX
SKU: B0GC6ZFC9L

$56

4180 640 0114 Trimmer Gear Head and 9" x 20T Chainsaw Tooth Brush Cutter Blade, 25-2 Trimmer Head Fit for Stihl Series FS91 FS91R FS111R FS131 FS131R FS111RX…

Bar length9"

CategoryGear Heads

Part numberB0GC6ZFC9L

ConditionNew — aftermarket replacement

What the listing states

Listed as compatible with: Stihl Series FS91 FS91R FS111R FS131 FS131R FS111RX FS111 FSA135R FSA135 Trimmer
Pieces in pack: 1

From our Amazon listing, checked September 25, 2026. Model and part-number matches are the seller's; confirm against the part on your machine.

Before you buy — how to verify fitment

Measure shaft diameter. Common sizes are 24mm, 25.4mm, and 28mm — check your trimmer manual or measure the drive shaft.
Count the splines. The gear head input must match your shaft spline count (typically 7 or 9).
Check output thread. Verify the thread direction and size for your cutting attachment.
Confirm your trimmer model against the compatibility list above.

Frequently asked questions

How do I know which gear head fits my trimmer?

Match the shaft diameter (typically 24mm, 25.4mm, or 28mm), the number of splines (7 or 9), and the thread direction on the output shaft. Check your trimmer manual for these specs.

Can I replace a gear head myself?

Yes. Remove the old head by loosening the clamp bolt, slide it off the shaft, and slide the new one on. Align the drive shaft splines, tighten the clamp, and check for wobble before running.