3 models in this file
Which BLACK+DECKER String Trimmer Fits Your Yard?
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BLACK+DECKER has established a long-standing reputation in the outdoor equipment market for creating straightforward, lightweight tools that prioritize usability over mechanical complexity. Homeowners, property managers, and travelers maintaining seasonal cabins appreciate the brand’s focus on low overall tool weights, clean electric operation, and manageable storage footprints that fit easily inside utility closets or vehicle trunks. Investing in reliable black and decker tools allows property caretakers to complete perimeter cleanup quickly without the mess, fumes, or maintenance demands of mixing two-cycle fuel.
A comprehensive black decker string trimmer comparison reveals that these six selections cater to distinctly different yard scales and power needs, spanning an ultra-portable 20V battery model, an uninterrupted corded electric unit, and heavy-duty 40V options in both bare-tool and complete kit configurations alongside factory line spools.
The line-up at a glance
BLACK+DECKER String Trimmers Compared
| Model | Power Source | Cutting Swath | Speed | Weight |
|---|---|---|---|---|
| LST300 | 20V MAX Battery | 12 inches | 6200 RPM | 5.7 pounds |
| BESTA510 | 6.5-Amp Corded Electric | 14 inches | 8000 RPM | 6.3 pounds |
| LST136B | 40V MAX Battery (Bare Tool) | 13 inches | 1400 RPM | Not listed |
| LST140C | 40V MAX Battery | 13 inches | Not listed | 6.4 pounds |
| LST136 | 40V MAX Battery | 13 inches | 8500 RPM | 7.8 pounds |
| AF-100-32P | Factory-Wound Spool | 0.065-inch line | Not listed | 4.64 ounces |
No. 1 of 3 · Black+Decker
BLACK+DECKER 20V MAX String Trimmer for Portable Yard Upkeep
8.8/10 Our score
Best for: Small yards and lightweight cabin upkeep
What the listing says
- 6200 RPM The POWERDRIVE Transmission delivers more power from the motor to the cutting string so you can…
- The Automatic Feed Spool – AFS automatically feeds trimmer line when needed with no bumping required
- 2-in-1 Trim or Edge – easily converts from trimmer to edger in seconds
- It is quiet and easy to start, delivering great cutting results without the mess and hassles…
- Lightweight design with adjustable handle and height positions provide maximum comfort and control of this grass…
- Battery powered weed eater includes (1) 2.0 Amp hour lithium ion battery pack for 33% more…
Pros
- Lightweight 5.7-pound build
- Automatic line feeding
- Wall-mountable charging base
Cons
- Narrower 12-inch cutting swath
The BLACK+DECKER 20V MAX String Trimmer (model LST300) delivers balanced cutting capability suited for everyday residential maintenance and secondary homes. Operating on an included 2.0-amp-hour lithium-ion battery, this unit provides 33 percent more runtime per pack than the earlier LBXR20 battery pack. It starts instantly without pulling cords or handling gasoline, providing a quiet cutting experience that will not disturb neighbors at vacation spots or quiet suburban developments. The system includes a wall-mountable charging base to conserve floor space in compact storage sheds or camper bays.
Power transmission is managed through the company’s POWERDRIVE system, which channels motor output directly to the cutting string to maintain a constant 6200 RPM through dense grass and weeds. Its 12-inch cutting swath offers nimble maneuvering between raised garden beds, patio borders, and narrow fence lines. When lawn edges require crisp definition along sidewalks, the 2-in-1 trim or edge mechanism allows users to switch modes in seconds without auxiliary hand tools. This black decker 20v max string trimmer delivers dependable utility across smaller residential spaces.
Weighing only 5.7 pounds, the LST300 is the lightest fully assembled string trimmer in this lineup, reducing arm strain during overhead trimming or sloped yard clearing. An adjustable auxiliary handle and multiple height positions ensure handlers of various heights can work comfortably. Its Automatic Feed Spool (AFS) continuously feeds cutting monofilament using centrifugal force, doing away with the need to strike the tool head against hard ground. This model is ideal for cabin owners and casual gardeners who prioritize lightweight maneuverability over wide swath coverage.
No. 2 of 3 · Black+Decker
BLACK+DECKER Weed Wacker with Auto Feed for Continuous Power
8.8/10 Our score
Best for: Continuous yard work near electrical outlets
What the listing says
- 2 in1 Trimmer Edger with wheeled edge guide – just rotate to convert from trimmer to…
- Weedeater edge trimmer features Automatic feed spool technology which eliminates bumping for hassle-free line feeding that…
- The 6.5 amp motor and POWERDRIVE Transmissionon the grass trimmer provide maximum performance when trimming through…
- Lightweight design with adjustable handle and height positions provide maximum comfort and control
- Cord retention system on electric string trimmer prevents accidental cord disconnection
- 14 in. cut path gets the job done fast
Pros
- Fast 8000 RPM motor
- Wide 14-inch cutting path
- Wheeled edge guide
Cons
- Requires continuous extension cord connection
The BLACK+DECKER Weed Wacker with Auto Feed (model BESTA510) provides continuous electric operation for yards where an outdoor power outlet is readily available. Driven by a 6.5-amp electric motor spinning at 8000 RPM, this corded weed eater cuts aggressively through tough overgrowth, unruly grass, and persistent weeds. Because it draws power straight from an extension cord, operators can work indefinitely without pausing to swap or recharge batteries.
This black decker corded string trimmer includes an integrated cord retention system designed to prevent frustrating disconnections when moving past landscaping shrubs. It features a wide 14-inch cutting swath, the broadest cutting diameter among the trimmers reviewed here, allowing you to finish large swaths of open lawn in fewer passes. Transitioning to edging duties is simple: the tool features a wheeled edge guide that stabilizes the head along sidewalks, driveways, and garden borders, yielding neat trench edges without scalping the turf.
At 6.3 pounds, the BESTA510 remains manageable for long sessions, and its adjustable handle and telescoping shaft adapt quickly to different operator heights. The Automatic Feed Spool system supplies line automatically without bumping interruptions. For property owners maintaining a tidy perimeter near exterior electrical outlets, this black and decker weed wacker delivers relentless cutting speed that gives way only when cordless portability is mandatory.
No. 3 of 3 · Black+Decker
BLACK+DECKER 40V MAX String Trimmer for Existing Battery Setups
8.8/10 Our score
Best for: Heavy overgrowth requiring fast turnaround charging
What the listing says
- High-Performance Battery The 40V MAX* Lithium Ion battery features a state of charge indicator, keeping your electric weed…
- High-Torque Transmission Power drive technology delivers impressive cutting strength at the string, ensuring clean and swift cuts with…
- Quick Conversion Effortlessly switch from trimming to edging in seconds for maximum versatility with this cordless edger
- Automatic Line Feeding The AFS system supplies trimmer line automatically, so your weed wacker cordless keeps working smoothly without…
- Wall Mountable Charging Base Convenient charging base can be mounted on the wall to save space and keep your tool…
- Ideal for Overgrowth: Great weed trimmer tackling areas of thick grass and weeds after mowing to…
Pros
- High-speed 8500 RPM motor
- Two-hour fast charger included
- Telescoping pole with soft grip
Cons
- Heaviest model at 7.8 pounds
Best for: Thick growth needing visible battery monitoring
Pros
- State of charge indicator
- Wall-mountable charger included
- High-torque PowerDrive transmission
Cons
- RPM speed not listed
Best for: Owners who already possess 40V batteries
Pros
- Power Command dial
- Torque-boosting transmission
- 3-year limited warranty
Cons
- Battery and charger not included
The BLACK+DECKER 40V MAX String Trimmer (model LST136B) is packaged as a bare tool, making it an efficient choice for homeowners who already own 40V MAX lithium-ion batteries and chargers. Designed with a 13-inch cutting width, this model handles larger clearing tasks that surpass the stamina of lower-voltage machines. The package includes an AF-100 spool, cutting guard, and auxiliary handle, ensuring complete mechanical readiness as soon as you slide in a compatible battery pack.
A standout attribute of this black decker 40v max string trimmer is its Power Command dial, which gives users immediate control over motor output. Turning the dial toward maximum power delivers forceful cutting strength to tackle thick weeds and woody stems, while switching to the runtime setting conserves battery energy across expansive, light-growth zones. Torque multiplication is delivered through the POWERDRIVE transmission, driving the cutting line at 1400 RPM while maintaining solid cutting resistance through dense debris.
The LST136B converts quickly from a grass trimmer into an edger for maintaining crisp boundaries along walkways and driveways. The automatic feed spool feeds fresh string reliably without manual adjustments, preserving your work rhythm across large properties. Although the listing does not specify the exact bare-tool weight, the unit features a balanced shaft layout supported by a 3-year limited warranty. It represents an ideal upgrade for users invested in the manufacturer’s 40V battery line.
From the notebook
Black+Decker 40V MAX 13 Inch String Trimmer Kit for Battery Visibility
Supplying immediate out-of-the-box trimming power, the Black+Decker 40V MAX 13 Inch String Trimmer (model LST140C) comes complete with a 40V MAX lithium-ion battery and a wall-mountable charging base. The battery features an integrated state-of-charge indicator that displays available power reserves at all times, preventing unexpected shutdowns at distant edges of a large property. Weighing 6.4 pounds, this model combines the physical agility of smaller trimmers with the extra muscle of higher-voltage battery engineering.
The high-torque PowerDrive transmission prevents motor stalling when encountering thick, neglected summer overgrowth. Its 13-inch cutting swath offers a balanced compromise between open-area coverage and controlled cutting around fence lines and landscaping stones. Line advancement is handled entirely by the AFS system, which automatically feeds monofilament line smoothly without requiring ground bumping.
Conversion from a grass trimmer to a vertical edger takes seconds, providing sharp definition along curbs, patios, and garden borders. The wall-mountable charging cradle keeps your gear organized and off workbench surfaces in packed garages or off-grid sheds. Supported by a 3-year limited warranty, the LST140C is well suited for homeowners seeking full 40V power with real-time battery tracking, though the listing does not specify its maximum rotational RPM speed.
From the notebook
BLACK+DECKER 40V MAX 13 in String Trimmer Kit for Fast Turnarounds
The BLACK+DECKER 40V MAX 13 in String Trimmer Kit (model LST136) offers maximum cutting speed and rapid charging. Equipped with a 40V MAX lithium-ion battery featuring an integrated state-of-charge indicator, this kit includes a dedicated fast charger that completely recharges the battery in two hours or less. This expedited turnaround makes the kit practical for vacation home managers who need to service multiple yard areas on a strict timeline.
Operating at speeds up to 8500 RPM, this trimmer delivers the fastest cutting head speed in this lineup, making short work of heavy stalks, dense reed grass, and tough weeds. The onboard PowerCommand dial lets you alternate between high-speed muscle for heavy overgrowth and extended runtime for light boundary work. The POWERDRIVE transmission directs steady mechanical force into the 13-inch cutting swath, maintaining high rotational momentum through thick growth.
An adjustable telescoping pole and soft-grip handle allow users of different heights to find a comfortable, ergonomic posture during long trimming sessions. At 7.8 pounds, it is the heaviest model reviewed, but that weight reflects its high-speed motor assembly and durable telescoping components. With quick conversion to edging mode, AFS automatic feeding, and rapid turnaround charging, this model is built for property owners with challenging overgrowth.
From the notebook
BLACK+DECKER Weed Eater String Spools for Seamless Replacement
Best for: Quick spool changes without hand winding
Pros
- Factory-wound tangle-free line
- Three spools with 90 feet total
- Broad multi-trimmer compatibility
Cons
- Limited to 0.065-inch trimmer heads
Even the most powerful trimmer relies on durable line, and the BLACK+DECKER Weed Eater String three-pack (model AF-100-32P) supplies authentic factory replacement line that eliminates hand-winding hassles. Each spool contains 30 feet of factory-wound 0.065-inch diameter line, delivering 90 feet of total trimming capacity. Because the line is wound evenly under machine tension, it feeds smoothly without the snarls and binding that frequently plague manually wound spools.
This authentic black decker trimmer line replacement pack works alongside the company’s Automatic Feed System, which uses centrifugal force to advance cutting line as it wears down against obstacles. The AF-100 spool fits a wide range of trimmers, including the LST300, BESTA510, LST136, LST136B, and LST140 models. Using genuine spools protects internal head components and ensures consistent feeding action.
Weighing only 4.64 ounces for the complete three-pack, these compact spools store neatly in utility drawers, tool bags, or vehicle compartments. The spools carry a 2-year limited warranty, guaranteeing manufacturing quality and material reliability. Keeping factory-wound spools nearby ensures quick, hassle-free line changes so you can complete edge work without frustration.
Before you choose
How to Choose the Right BLACK+DECKER String Trimmer
Selecting which black decker trimmer to buy begins with assessing your yard’s layout, access to electrical power, and tool storage space. For small residential lawns, urban townhomes, and rental cabins, the 20V MAX LST300 offers exceptional portability. Weighing only 5.7 pounds, it packs easily into a trunk or utility closet and delivers enough runtime to trim light edges without physical strain.
If you have accessible outdoor outlets and prefer continuous cutting without managing batteries, the corded BESTA510 is an excellent choice. Its 6.5-amp motor, 8000 RPM cutting speed, and broad 14-inch path cut wide strips of turf efficiently. When finishing outdoor chores at a summer cabin, putting away an electric trimmer lets you step inside to relax near a black and decker portable air conditioner without tracking in fuel odors.
For large acreages and thick brush, the 40V MAX lineup provides the required cutting strength. If you already own compatible 40V tools, the LST136B bare tool saves space and equipment redundancy. If you need a complete kit, the LST140C offers a battery fuel gauge, while the LST136 provides an 8500 RPM motor and a two-hour fast charger. After clearing expansive fence lines on hot summer days, cooling off inside an outbuilding cooled by a black and decker 14000 btu portable air conditioner makes yard maintenance far more enjoyable.
Line management also plays a crucial role in overall convenience. Every trimmer in this review features an Automatic Feed Spool (AFS) mechanism that advances line via centrifugal motion, eliminating the need to bump the tool against the turf. Keeping genuine AF-100 factory spools on hand prevents line welding and ensures your black decker string trimmer operates reliably season after season.
Questions people ask
FAQ
How does the Automatic Feed Spool system work on a BLACK+DECKER string trimmer?
The Automatic Feed Spool (AFS) mechanism uses centrifugal force to advance fresh monofilament line as you cut. When the line wears down or snaps, the reduced centrifugal resistance triggers an internal mechanical release, feeding a fresh length of line without requiring manual ground bumping.
Can 20V MAX and 40V MAX batteries be swapped between tools?
No, 20V MAX and 40V MAX battery packs are completely distinct platforms. They use different internal voltage setups and incompatible connector terminals, meaning a 20V tool like the LST300 cannot run on a 40V battery, and 40V models cannot accept 20V packs.
What diameter line does a BLACK+DECKER weed wacker use?
The string trimmers covered in this lineup use standard 0.065-inch diameter cutting line. Factory replacement spools, such as the AF-100-32P pack, come wound with 30 feet of 0.065-inch monofilament per spool to ensure smooth feeding through the centrifugal AFS mechanism.
Is a corded or cordless BLACK+DECKER string trimmer better for travel properties?
Cordless trimmers offer clear benefits for remote cabins because they do not require exterior outlets or long extension cords. However, for secondary homes left unattended for months, a corded model like the BESTA510 eliminates concerns about battery drain or cell degradation during extended idle periods.
How do you switch these trimmers into lawn edger mode?
These 2-in-1 tools convert easily by rotating the shaft or head assembly. Certain models, like the BESTA510, feature an integrated guide wheel to stabilize the cutting line along sidewalks, while cordless models like the LST300 and LST136 rotate along the main shaft to position the line vertically for clean edging.
Prices, specifications and the feature lines above are read from the product listing and can change without notice. Scores are out of 10, based on listed specifications and buyer feedback; nothing on this page is written from handling the product.
