Black & Decker 40V MAX 13 in. 2-in-1 Cordless String Trimmer/Edger with POWERCOMMAND Kit

Why I reached for the Black & Decker 40V trimmer

I spend a lot of time fussing over the last 10% of yard work—the fence lines, around beds, under the deck stairs, and those sidewalks that always seem to creep over with turf. I wanted something light, simple, and cordless that wouldn’t fight me. After several weekends with the Black & Decker 40V trimmer, I’ve got a clear picture of where it excels, where it compromises, and who will be happiest with it.

Setup and first impressions

Out of the box, assembly is straightforward: attach the guard, click on the auxiliary handle, load the prewound spool, and you’re ready. The included fast charger brought the 40V battery from empty to full in just under two hours in my shop, which lines up with the spec. The battery’s state-of-charge indicator is a small but meaningful touch—I check it before I head outside and avoid the classic mid-trim dead stop.

The tool itself feels decidedly light for a 40V unit. At around nine pounds with the battery, it’s easy to maneuver and doesn’t ask much of your back or shoulders. The plastics are what you’d expect in this class—functional, not fancy—but the molding is clean and the guards line up properly. The battery slides into the bay with a firm click; fitment is snug on my unit, which I prefer because it won’t wiggle loose during use.

Ergonomics and balance

Balance matters more than raw weight on string trimmers, and this one is well tuned. The battery sits close to the grip, so the nose doesn’t feel heavy even with the guard on. The auxiliary handle adjusts quickly and stays put—you can set it low for edging or higher for trimming and never feel like you’re overreaching. I ran it for multiple sessions without sore wrists or the “one-more-pass” fatigue that heavier units bring.

Noise is comfortably low for a trimmer in this class, and the vibration is modest. If you’re used to gas, you’ll appreciate how much less buzz reaches your hands.

Power and cutting performance

The heart of the experience is the power dial, which lets you bias for runtime or for cutting muscle. On the low-to-mid settings, I had no trouble maintaining lawn edges, cleaning up around pavers, and shaving back stray tall grass. Push the dial toward max and the motor spins up with enough authority to slice through denser clumps and slightly woody stems typical of neglected corners. The transmission transfers torque efficiently; you can hear the motor dig in without bogging immediately.

It’s a 13-inch cutting swath, which is ideal for small-to-medium lawns. You’ll make more passes on acreage, but for a typical suburban yard, the width is a good compromise between precision and productivity.

This is still a residential trimmer. It isn’t going to replace a contractor-grade unit with thicker line and a bigger head. On stubborn, waist-high weeds and heavy thatch, I needed to slow down and make a couple of methodical passes to get a clean cut.

Line feed and head design

The automatic feed spool is the convenience feature that pays off every minute you use the tool. There’s no bumping—the head meters out line automatically to maintain cutting length. In practice, it worked reliably and saved me from the frequent stop-and-start adjustments that cheaper heads require.

There is a trade-off: automatic systems tend to consume line a bit faster than manual bump heads. I went through more line than I typically do with a bump-to-feed pro trimmer. The upside is consistent cut quality and fewer interruptions. Replacing the spool is a tool-free job that takes under a minute. If you trim often, consider having a spare spool on hand so you can swap and finish the job instead of rethreading mid-session.

Edging mode

The conversion from trimming to edging is quick—rotate the head, adjust your handle position, and you’re ready to trace the sidewalk. For maintenance edging (where you’re keeping an already-clean edge), it’s effective and tidy. The trimmer rides predictably and flings debris away from your legs with the guard in place. If you’re trying to reclaim a wildly overgrown curb, you’ll need patience and possibly a dedicated edger for the first pass. After that, the trimmer is perfectly capable of weekly touch-ups.

Battery life and charging

The included 40V lithium-ion pack is rated at 1.5 Ah. In real use, with the dial bouncing between the middle and higher settings, I consistently saw 20–25 minutes of trimming per charge. Dial it back for light work and you can stretch beyond that; pin it at maximum for thick growth and you’ll land closer to 15–20 minutes. That’s enough to do a typical front-and-back yard for me, including a quick edge. If your property is larger, budgeting for a second battery is a smart move. The fast charger is genuinely fast and compact, and it’s wall-mountable, which keeps it out of the way in a small shop.

Build quality and reliability notes

For a plastic-bodied residential trimmer, the build feels solid. The head locks positively in both trim and edge positions, and the guard doesn’t flex excessively. The control dial and trigger have a reassuring resistance that doesn’t scream “cheap.”

A couple of practical notes from my time with it:
- The battery bay is tight by design. Seat the battery with a straight push until you hear a click; if it stops short, don’t force it at an angle.
- Keep the head clean. Grass sap and dust can gunk up the auto-feed over time. A quick brush-out after each session kept mine feeding smoothly.
- As with most lightweight trimmers, the line itself is the limiting factor. If you’re constantly hitting chain-link or stone, expect to replace line more frequently.

Who it’s for

• Homeowners with small to medium yards who want a light, no-fuss trimmer that can also edge.
• Anyone prioritizing ergonomics and low noise over brute force.
• Users already in (or willing to start) a simple 40V battery setup and who appreciate the grab-and-go convenience.

Who should look elsewhere

• Those managing large properties or routinely tackling heavy brush and thick, woody growth. A wider cutting head with heavier line on a more powerful platform will be faster and more durable.
• Users who need 45–60 minutes of continuous trimming on a single battery. You can absolutely make this work with multiple batteries, but a larger-capacity pack or different platform might be more efficient.

Tips for better results

• Use the power dial intentionally: low for lawn edges and delicate beds, high for dense patches. It notably extends runtime when you’re not over-spinning the head.
• Keep a spare spool ready. The convenience gain is significant when you run out mid-job.
• Let the line do the work. If you’re forcing the head into thick vegetation, you’ll burn line faster and stress the motor.
• Check the battery indicator before starting and top off if you’re below half. The short charge time makes opportunistic charging easy.

The bottom line

The Black & Decker 40V trimmer hits a sweet spot for residential yard care: light in the hand, simple to operate, and capable enough to handle the typical mix of trimming and edging without fuss. The automatic feed, adjustable power, and fast-charging battery make it a genuinely convenient tool for weekly maintenance. It won’t replace a pro-grade machine for rough cutting, and you’ll go through line a bit faster than with a bump head, but the trade-offs make sense for homeowners who value ease and ergonomics over raw power.

Recommendation: I recommend this trimmer for homeowners with small to medium lawns who want a comfortable, straightforward cordless tool for routine trimming and edging. It’s easy to live with, delivers respectable cutting performance for its size, and the included fast charger and battery get you working quickly. If you regularly tackle heavy brush or need long, uninterrupted runtimes, consider a higher-capacity system or plan on adding a second battery.