HART 40V Brushless Carbon Fiber String Trimmer Review

HART 40V Brushless Carbon Fiber String Trimmer Review

HART Moves Up The Charts With Brushless Carbon Fiber String Trimmer

Your lawn mower can leave the best-looking cut in the neighborhood but it doesn’t mean much if you don’t trim and edge. The problem is high-performance string trimmers can strain your back and lightweight ones tend to lack the muscle to do the job quickly. We tested the HART 40V Brushless Carbon Fiber String Trimmer to see if it can bring balance to the force.

Using the HART 40V Brushless Carbon Fiber String Trimmer


Compared to HART’s earlier string trimmer, we were impressed with the performance of this model. It’s strong enough to spin line up to 0.095-inch and was able to cut through neglected areas easily. It’s not strong enough to handle the thick stuff we tackle out at the ranch, but any of your typical lawn grasses and weeds are no match.

HART 40V Brushless Carbon Fiber String Trimmer

The vibration levels are lower than we expect from gas trimmers. However, some of the premium residential and professional models reign it in more.

When it comes to runtime, we were able to trim for just over 28 minutes on the 4.0Ah battery that comes in the kit. That’s running at high speed with 0.095-inch line in the longer cutting position. That’s enough to cover most lawns up to a 1/2-acre. The nice thing is HART includes is a fast charger that gets you back in the game 3 times faster than the standard 40V charger.

Attachment Capable

This trimmer is attachment capable and HART uses a universal attachment connection. It works with all HART PowerFit attachments and any other universal attachments you might have.

Universal attachment connection

As an added bonus, the 3-position detent makes it easy to turn the string trimmer 90° and edge without messing with the handle ergonomics.

3-in-1 Bump Feed Head

HART includes a 3-in-1 trimmer head with this model. The standard head has a reversible cutter that you can set to 13 inches for tighter areas and longer runtime or 15 inches for larger areas and faster cutting.

There’s a second attachment for the head you can swap out that gives you a pair of plastic grass-cutting blades. These have more mass and can get through some of the stalkier grasses better than trimmer line. They’re more likely to damage paint and other soft materials, so be aware of what’s around you when you use them.

3-in-1 trimmer head

Weight and Balance

The big deal about switching the shaft to carbon fiber is weight savings and we could tell the difference while we were using it. If you’re skeptical about carbon fiber as a shaft material, we can confidently recommend it. Every string trimmer we’ve used with it has held up great over time and we’re not worried about HART having any issues in that department.

HART 40V Brushless Carbon Fiber String Trimmer

The bare weight of the trimmer is 8.8 pounds and a 4.0Ah battery brings the total package up to 11.1 pounds. While that’s not the lightest we’ve seen, it is a very reasonable weight for the performance level we’re seeing and you can shave a bit more off by using a lower-capacity battery.

With that battery and the brushless motor in the powerhead, the balance is definitely toward the back. That’s normal for attachment-capable string trimmers and wasn’t a pain point for our team.

Additional Highlights

  • Works with all HART 40 batteries

HART 40V Brushless Carbon Fiber String Trimmer Price

You can find this HART string trimmer at Walmart in-store and online for $248. The kit includes the trimmer, 4.0Ah battery, and fast charger (3x faster than HART’s standard charger). HART warranties the tool for 5 years and the battery for 3.

The Bottom Line

HART balances performance and weight very well with its 40V Brushless Carbon Fiber String Trimmer. It helps push HART’s outdoor power equipment line forward, signaling the brand is ready to reach homeowners that want higher-performing lawn care tools.


  • Model: HART HLST051VNM
  • Power Source: HART 40V battery
  • Cutting Swath: 13 – 15 inches
  • Max Line Diameter: 0.095-inch
  • Weight: 8.8 pounds bare, 11.1 pounds with 4.0Ah battery
  • Warranty: 5 years
  • Price: $248 kit with 4.0Ah battery and fast charger

Check out all of HART’s lawn and garden tools here.

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