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String Trimmer & Brush Cutter Parts

What parts are included in this collection? Mow Town USA offers replacement string-trimmer and brush-cutter parts, including trimmer heads, replacement spools, bump knobs, head covers, cutting blades, blade adapters, washers, nuts, bolts, reducer bushings and related mounting hardware.

Shop by the original equipment part number, trimmer brand, model number, thread direction, arbor size, blade diameter and mounting style. Before ordering, compare the replacement part with the original component and verify every listed measurement.

How to Choose the Correct Trimmer or Brush-Cutter Part

1. Identify the exact component

  • Trimmer heads: complete cutting-head assemblies for compatible string trimmers and brush cutters.
  • Spools and bump knobs: replacement internal or external head components used to feed cutting line.
  • Head covers and bases: housings and retainers that protect and secure compatible spool assemblies.
  • Brush-cutter blades: metal or polymer cutting attachments designed for compatible equipment and approved applications.
  • Adapters, bushings and washers: mounting components that help match a blade or head to the equipment shaft and hardware.
  • Nuts and bolts: fasteners that secure compatible cutting attachments and head components.

2. Match the OEM or replacement part number

The original equipment part number is usually the most reliable starting point. Check the trimmer manual, illustrated parts diagram or number printed on the original head, spool, knob, blade or mounting component.

3. Confirm the shaft thread and direction

Trimmer heads and mounting nuts can use different thread sizes and may be right-hand or left-hand threaded. Match the thread diameter, pitch and direction before ordering. A part that appears similar might not attach correctly.

4. Check the arbor and mounting-hole size

Brush-cutter blades and adapters are commonly identified by blade diameter and center-hole or arbor size. Compare both measurements with the original equipment and confirm that the blade is approved for the trimmer or brush cutter.

5. Compare head type and line-feeding design

Replacement heads may use bump-feed, fixed-line, semi-automatic or fast-loading designs. Confirm that the mounting system, rotation direction, line capacity and operating design match the equipment.

6. Verify blade diameter and intended use

Use only a blade type and diameter approved by the equipment manufacturer. Brush, grass and polymer blades are designed for different cutting conditions and require compatible guards, handles and mounting hardware.

7. Inspect related mounting hardware

When replacing a head or blade, inspect the washer, nut, bolt, adapter, cover and retaining parts. Worn, cracked, bent or missing hardware can prevent secure installation.

Frequently Asked Questions

How do I know which trimmer head fits my equipment?

Match the original part number, shaft thread, thread direction, mounting style, rotation direction and any equipment applications shown in the product listing.

Are string-trimmer heads universal?

No. Some heads include adapters for several applications, but thread size, shaft style, rotation and guard requirements differ between machines.

What is the difference between a spool and a complete trimmer head?

A spool holds the cutting line inside a compatible head. A complete head normally includes the housing and feed mechanism, although included components vary by product.

How do I select a brush-cutter blade?

Confirm the blade diameter, center-hole or arbor size, blade style, rotation direction and equipment approval. Use the required guard and mounting hardware specified by the equipment manufacturer.

What does left-hand thread mean?

A left-hand threaded fastener tightens in the opposite direction from a standard right-hand thread. Match the original thread direction exactly.

Can I install a metal blade on any string trimmer?

No. The equipment must be designed and approved for that blade type. The correct guard, handle, harness, gearbox and mounting hardware may also be required.

Should I replace the mounting hardware with the cutting attachment?

Replace hardware that is worn, damaged, bent, cracked, stripped or missing. Confirm that every component matches the equipment and attachment specifications.

Where can I find replacement trimmer line?

Cutting line is available separately in our String Trimmer Line collection, organized by diameter, shape and package format.

How can I reduce the chance of ordering the wrong part?

Provide the equipment brand, model number, original part number, shaft or thread measurements and clear photos of the original component. Compare the specifications rather than relying only on appearance.

Find the Right Trimmer Replacement Part

Review each product listing for part number, thread size, arbor size, dimensions, mounting style and equipment application. For additional guidance, visit our Frequently Asked Questions page or contact Mow Town USA with your equipment information.

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Rotary # 8802 BLADE BOLT NUT 10-24 WALKER Pack of 10

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Fits Walker. Fits Rotary 6793 Blade Hub. Used with Rotary 8801 Bolt. Zinc Plated, Low Carbon Steel.Replaces:WALKER F002Dimensions: THREAD SIZE: ...

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Rotary # 50507 BRUSH CUTTER BLADE 300MM X 25.4MM UNIVERSAL

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Universal Formed Mulching Brush Cutter Blade. Used on machines that accept 25.4mm center hole.Dimensions: LENGTH: 300 mm C. H. DIA: 25.4000 mm THIC...

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Rotary # 11988 TRIMMER HEAD SEMI MATIC KT30 BUMP-N-FEED

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KWIK Loader Model KT30 Dual Line, Semi-Matic, Bump-N-Feed Trimmer Head with adapters included. See Rotary 13300 for Dual Compartment Spool.Dimensi...

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Rotary # 9182 NUT 10 X 1.25 MM LH ECHO Pack of 5

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Blade/Head Nut for Echo fits Weedtrimmers, Brushcutters -for Mounting Blades or Heads. Order in multiples of (5).Replaces:ECHO 90051100010Dimensio...

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Rotary # 50504 BRUSH CUTTER BLADE 300MM X 20MM UNIVERSAL

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Universal Formed Mulching Brush Cutter Blade. Used on machines that accept 20mm center hole.Dimensions: LENGTH: 300 mm C. H. DIA: 20 mm THICKNESS: ...

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Rotary # 50409 14" X 1" BRUSHCUTTER BLADE

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Dimensions: LENGTH: 14" WIDTH: 3-1/2" C. H. DIA: 1" THICKNESS: 0.0950" CASE QTY: 2160 PALLET QTY: 1

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Rotary # 14501 BASE COVER FOR TRIMMER HEAD

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Cover replaces Stihl 4002-713-9708. Cover Base to fit Stihl Autocut 25-2 Trimmer Head. Fits Stihl Models FS 44, 55, 80, 83, 85, 90, 100, 100RX, 110...

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Rotary # 14500 SPOOL FOR TRIMMER HEAD

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Spools replaces Stihl 4002-713-3017. Spool to fit Stihl Autocut 25-2 Trimmer Head. Fits Stihl?« Models FS 44, 55, 80, 83, 85, 90, 100, 100RX, 110...

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Rotary # 13377 TRIMMER HEAD FAST LOADING 450

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Trimmer Head 450 Fast Loading. Replaces Shindaiwa 78890-21001. 4-1/2" Diameter.Replaces:SHINDAIWA 78890-21001Dimensions: DIAMETER: 4-1/2" CASE QTY...

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Rotary # 8521 BUMP HEAD KNOB HOMELITE

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The Rotary #8521 Bump Head Knob is a high-quality aftermarket replacement for the Homelite/Jacobsen A97910A. This red knob is designed specifically...

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Rotary # 9743 BRUSH BLADE 12"

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Dimensions: DIAMETER: 12" THICKNESS: 3 mm BORE: 1"/25mm TEETH: 3 CASE QTY: 25 PALLET QTY: 48

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Oregon 20-020 Magnum Gatorline SuperTwist Trimmer Line .095 in. x 282 ft.

Oregon
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Oregon Magnum Gatorline SuperTwist Trimmer Line combines a high-strength inner core, a weld-resistant outer layer, and an aerodynamic twisted profi...

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Rotary # 12820 TRIMMER LINE CUTTER Pack of 5

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Trimmer Line Cutter. *Patented* Simple to use and safe with no exposed cutting edges. Put on your key ring and have ready when it is time to refill...

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Rotary # 7860 REDUCER BUSHING 3/4" Pack of 10

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Fits Rotary #7854, 7855, 4413, 4414, 7862 & 7863. (Plastic)Dimensions: CASE QTY: 2000 PALLET QTY: 60

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Rotary # 9035 BLADE TRIMMER WEED BLASTER 4"X 31/64" Pack of 3

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Steel inserted Plastic Blade. Fits Grasscraft GC1601 & Allen SE1601. Hover Mower 1601-12Replaces: ALLEN SE1601 GRASSCRAFT SE1601 Dimensions: L...

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Rotary # 7141 POLY BLADES FOR STIHL Pack of 12

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Interchanges with Husky 531-01-77-15 Blades.Replaces:STIHL 4111-007-1001Dimensions: LENGTH: 4-1/16" C. H. DIA: 0.4750" CASE QTY: 1500 PALLET QTY: 36

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Rotary # 17141 POLY BLADES (3) FOR STIHL (BAGGED) Pack of 5

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Interchangeable with Husky 531-01-77-15 Blades.Dimensions: LENGTH: 4-1/16" C. H. DIA: 0.4750" CASE QTY: 5 PALLET QTY: 252

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Rotary # 8801 BLADE BOLT 10-24 X 1" WALKER Pack of 10

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Used on Blade Hub on Walker. Stainless Steel.Replaces:WALKER F202Dimensions: LENGTH: 1" THREAD SIZE: 10-24 CASE QTY: 2500 PALLET QTY: 90

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Rotary # 8455 BLADE BAR WASHER 1/2" SNAPPER Pack of 10

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Fits Snapper. Internal Slotted. Fits Rotary Blade Bar #5847.Replaces: SNAPPER/KEES 9-0509 SNAPPER/KEES 7090509 SNAPPER/KEES 7090509YP Dimensions:...

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Rotary # 8454 BLADE BAR NUT 1/2" SNAPPER Pack of 10

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Fits Snapper. Fits Rotary Blade Bar #5847.Replaces: SNAPPER/KEES 9-0559 SNAPPER/KEES 7090559 SNAPPER/KEES 7090559YP SNAPPER/KEES 703903 Dimensions...

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Rotary # 8453 BLADE BAR BOLT 1/2"X 1"SNAPPER Pack of 10

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Fits Snapper. Fits Rotary Blade Bar #5847.Replaces: SNAPPER/KEES 9-0392 SNAPPER/KEES 7090392 SNAPPER/KEES 7090392YP SNAPPER/KEES 703880 Dimensions...

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Rotary # 1218 FIBRE WASHER 1" X 2-5/16" Pack of 10

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Fibre Washer 1" X 2-5/16"Dimensions: SIZE: 1" X 2-5/16" CASE QTY: 750 PALLET QTY: 100

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Rotary # 1217 FIBRE WASHER 7/8" X 2-5/16" Pack of 10

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Fibre Washer 7/8" X 2-5/16"Dimensions: SIZE: 7/8" X 2-5/16" CASE QTY: 1000 PALLET QTY: 48

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Rotary # 1216 FIBRE WASHER 3/4" X 2-5/16" Pack of 10

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Fibre Washer 3/4" X 2-5/16"Dimensions: SIZE: 3/4" X 2-5/16" CASE QTY: 750 PALLET QTY: 48

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