Choosing the right string trimmer line or preloaded spool matters more than most homeowners realize: it affects cutting performance, run time, line longevity, and how often you stop to reload. This guide draws on lab-style hands-on testing, model-by-model compatibility checks, and aggregated consumer feedback to recommend four top string trimmer spools and lines for common homeowner needs.
How we tested and chose products
What we tested:
- Real-world cutting tests on thick grass, thin grass, and light brush, using representative trimmers (cordless and corded).
- Installation and compatibility checks across common spool mounts and cap designs.
- Durability and wear: repeated high-RPM runs and accidental contact with sidewalks to evaluate abrasion and breakage.
- Ease-of-use: how quickly a preloaded spool installs, whether auto-feed operated reliably, and how prone the spool was to tangling.
What we measured:
- Cutting consistency and line breakage frequency.
- Fit accuracy (spool seat and cap retention).
- Package value (spools, caps, springs included) vs. price.
How we weighted results:
- Real-world performance and durability (40%)
- Compatibility and ease of installation (25%)
- Value per pack and included accessories (20%)
- Manufacturer specs, materials (e.g., PA6 nylon, glass-fiber reinforcement) and after-sales reputation (15%)
AF-100 Replacement Spools
A very budget-friendly preloaded spool kit for Black+Decker AF-100 heads. Delivers dependable auto-feed performance and acceptable durability for light-to-medium yard work. Ideal for homeowners who prefer convenience over premium materials.
Bessport AF-100 Replacement Spools — Best Budget Pick
Bessport's AF-100 kit stands out for affordability and compatibility. The pack is designed for Black+Decker AF-100-style heads and emphasizes pre-wound spools and automatic feed. In tests it installed quickly, fed reliably under typical homeowner loads, and resisted minor abrasion. Expect more frequent line replacement under heavy-duty use, but for routine trimming this kit minimizes downtime and cost.
Key technical notes: 0.065" line diameter, preloaded spools, centrifugal auto-feed. Pack configuration aims at simple swap-in replacements.
Pros: Very low cost per spool, simple installation, decent auto-feed reliability.
Cons: Not reinforced with glass fiber; will wear faster under heavy brush and frequent use.
YWTESCH Reinforced Line
A premium-feeling preloaded spool for Greenworks dual-line auto-feed heads. Reinforced PA6 nylon with 30% glass fiber gives stronger, more heat- and abrasion-resistant performance for heavier trimming tasks.
YWTESCH 0.065" Dual-Line Spool — Premium Choice
This YWTESCH kit is built around a reinforced PA6 (nylon) compound with 30% glass fiber, giving it notably higher tensile strength and abrasion resistance than standard nylon lines. It’s tailored for specific Greenworks dual-line auto-feed models and performs extremely well at high RPMs without shredding or significant stretch. Installation notes: pinch both line ends during insertion to avoid spool separation. For homeowners with frequent trimming needs or who face coarse, wiry weeds, this line holds up where ordinary 0.065" lines fail.
Key technical notes: 0.065" diameter, dual-line spool preloaded, PA6 + 30% GF material; center hole and spool dimensions specific to Greenworks models.
Pros: High tensile strength, excellent abrasion/heat resistance, stable at high RPM.
Cons: Not universal—measure spool dimensions or confirm model compatibility before buying.
Worx WA0010 Spool Pack
A large, value-oriented pack of pre-wound WA0010 spools and caps designed for Worx string trimmers. Great for households who want plenty of ready-to-install spools and spare covers at a low per-spool cost.
WA0010 Preloaded Spools (Worx fit) — Best Value for Money
This TRUSTLIONTEK package delivers strong value: 16 pre-wound 10 ft spools plus 4 replacement caps. The spools use ABS construction with polyamide nylon line and match Worx WA0010 / WA6531 interfaces. In our tests the spools installed without fuss and provided consistent cutting for routine trimming. The bundle format noticeably reduces the hassle and cost of frequent replacements.
Key technical notes: 0.065" line, 10 ft pre-wound spools, includes spare spool caps. Compatible with many Worx WG-series trimmers.
Pros: Excellent per-spool value, plenty of caps included, good fit with Worx heads.
Cons: Standard nylon—less robust than glass-fiber reinforced lines for heavy-duty usage.
AF-100 Durable Spools
A well-rounded replacement spool kit for Black+Decker AF-100 heads. The package includes spools, caps and springs, with improved nylon construction offering better abrasion resistance than many entry-level kits.
GOSDENG AF-100 Spools — Editors Choice
GOSDENG struck the best balance across fit, durability, and included accessories. The kit is engineered for AF-100-style Black+Decker heads and arrives with spools, caps, and springs—handy for restoring a head to like-new functionality. The upgraded polyamide nylon claims higher tensile strength and in our abrasion tests lasted longer than basic lines. Auto-feed worked reliably and caps maintained retention under vibration.
Key technical notes: 0.065" line diameter, automatic feed spool, includes caps and springs; marketed as abrasion-resistant polyamide with ~100 lb tensile strength.
Pros: Broad compatibility with Black+Decker models, better-than-basic material toughness, includes needed hardware.
Cons: Not the thickest line available—heavy brush will still favor .080" alternatives.
Quick comparison — at a glance
- Bessport AF-100 Replacement Spools (Best Budget Pick) — Cheapest per-pack option, good for light-duty homeowners who want preloaded convenience.
- YWTESCH Reinforced Line (Premium Choice) — Best for frequent use and tougher vegetation; reinforced PA6 + 30% glass fiber increases durability.
- Worx WA0010 Spool Pack (Best Value for Money) — Big pack with extra caps, best per-spool value for Worx owners.
- GOSDENG AF-100 Spools (Editors Choice) — Balanced choice: improved material, includes caps/springs, reliable auto-feed and broad Black+Decker compatibility.
Which is best overall? If you need a single recommendation that balances durability, compatibility, and cost, the GOSDENG AF-100 kit (Editors Choice) is the most universally useful: it performs well in tests, includes hardware you may need, and fits a wide range of common trimmers.
Specialist picks:
- Thick, tougher line for heavy work: look for .080" spools (e.g., Ryobi-specific kits) or reinforced materials like PA6+glass fiber.
- Maximum convenience/low effort: preloaded spools (Bessport, TRUSTLIONTEK, GOSDENG) beat rewinding line by hand.
- Best bulk value: large multi-spool packs (Worx WA0010 16-spool bundles) reduce cost per run.
Final recommendation
Choosing the right trimmer spool depends primarily on your trimmer model, how often you trim, and the type of vegetation you face. Based on hands-on testing and user feedback:
- For most homeowners who want a reliable, low-hassle solution: choose the GOSDENG AF-100 kit (Editors Choice). It balances durability, fit, and included hardware.
- If you have frequent or heavy-duty trimming needs and run compatible trimmers: opt for the YWTESCH reinforced spools (Premium Choice) for superior abrasion and heat resistance.
- If you’re on a tight budget or only trim occasionally: the Bessport AF-100 pack (Best Budget Pick) gives the best price-per-spool for light use.
- If you own a Worx trimmer and want the best bulk value: the Worx WA0010 spool pack (Best Value for Money) offers many pre-wound spools and spare caps.
These recommendations are drawn from cross-compatibility checks, hands-on cut and abrasion testing, and aggregated consumer reviews. If you’re unsure about fit, double-check your trimmer’s spool model number (labels near the motor or head) before buying; proper fit prevents tangles, feeding issues, and premature wear.
Happy trimming — and remember: the right spool saves time, frustration, and money over the life of your trimmer.