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EGO Power+ ST1521S 15-Inch String Trimmer

EGO

EGO Power+ ST1521S 15-Inch String Trimmer

  • 15-inch cutting swath with POWERLOAD auto-feed line
  • 56V ARC Lithium battery, 2.5Ah included
  • Carbon fiber split shaft
  • Pivoting head for vertical edging
  • Brushless motor
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On this page

Is the EGO Power+ ST1521S 15-Inch String Trimmer worth it?

Yes, for the right buyer. The EGO Power+ ST1521S 15-Inch String Trimmer ranks #1 in our Best String Trimmers for Edging list. Its biggest strength: pivoting head locks cleanly into edging position without extra tools. The main caveat: 56V battery and charger add cost versus 40V competitors.

Overview

What the EGO Power+ ST1521S 15-Inch String Trimmer does well

Best overall for slopes. Its case rests on carbon fiber shaft keeps weight low without sacrificing reach on an incline and adjustable shaft length helps you stand on flatter ground and reach up a slope. Keep in mind that still needs two hands for full control, no single-handed operation on the steepest grades.

The clearest step up in build quality and cutting performance from budget models. 5Ah included. One caveat, near the top of this price band once accessories are added.

5Ah included. 0Ah or more) cost extra and are sold separately.

Specs that matter

Key features

  • 15-inch cutting swath with POWERLOAD auto-feed line
  • 56V ARC Lithium battery, 2.5Ah included
  • Carbon fiber split shaft
  • Pivoting head for vertical edging
  • Brushless motor
The trade-offs

Pros & cons

Pros

  • Pivoting head locks cleanly into edging position without extra tools
  • POWERLOAD auto-feed threads new line in seconds, useful after a long edging session wears the line down
  • 56V battery has enough torque to run the line against curb edges without bogging
  • Carbon fiber shaft keeps the tool light for one-handed edging control

Cons

  • 56V battery and charger add cost versus 40V competitors
  • Proprietary EGO battery doesn't cross over to other brands
  • No built-in guide wheel, so depth control is by feel
Fit check

Should you buy the EGO Power+ ST1521S 15-Inch String Trimmer?

Buy it if you're…

  • Shopping for edging
  • Shopping for steep hills and slopes
  • Shopping for budgets under $200
  • Shopping for thick weeds and overgrown lots
  • Shopping for small yards

Think twice if this matters to you

  • 56V battery and charger add cost versus 40V competitors
  • Proprietary EGO battery doesn't cross over to other brands
  • No built-in guide wheel, so depth control is by feel
Where it ranks

Featured in 5 best-of lists

ListRank
Best String Trimmers for Edging#1 / 5
Best String Trimmers for Steep Hills and Slopes#1 / 4
Best String Trimmers Under $200· Best overall#1 / 6
Best String Trimmers for Thick Weeds and Overgrown Lots#2 / 6
Best String Trimmers for Small Yards#3 / 5
Cross-shop

Alternatives to the EGO Power+ ST1521S 15-Inch String Trimmer

Products ranked near it in our research, each better for a slightly different buyer.

Head-to-head

Compared with

Buying advice: string trimmers

  1. Cordless suits most homes. Gas suits large or overgrown lots. Corded suits small yards.
  2. Bump feed releases line when you tap the head. Automatic feed is convenient but can waste line.
  3. Wider swaths cover more ground per pass. 13 to 16 inches suits most yards.
  4. Straight shafts reach under bushes and suit taller users. Curved shafts are lighter and easier to handle.
  5. Attachment-capable trimmers can take edgers, pole saws and cultivators.

Read the full guides

Answers

EGO Power+ ST1521S 15-Inch String Trimmer: common questions

Is the EGO Power+ ST1521S 15-Inch String Trimmer worth buying?

Yes, for the right buyer. The EGO Power+ ST1521S 15-Inch String Trimmer ranks #1 in our Best String Trimmers for Edging list. Its biggest strength: pivoting head locks cleanly into edging position without extra tools. The main caveat: 56V battery and charger add cost versus 40V competitors.

Who is the EGO Power+ ST1521S 15-Inch String Trimmer best for?

Based on our research it suits edging, steep hills and slopes, budgets under $200 and thick weeds and overgrown lots. It's ranked #1 of 5 in our Best String Trimmers for Edging list.

What are the downsides of the EGO Power+ ST1521S 15-Inch String Trimmer?

The main trade-offs owners and reviewers point to: 56V battery and charger add cost versus 40V competitors; proprietary EGO battery doesn't cross over to other brands; no built-in guide wheel, so depth control is by feel.

What are the key features of the EGO Power+ ST1521S 15-Inch String Trimmer?

15-inch cutting swath with POWERLOAD auto-feed line, 56V ARC Lithium battery, 2.5Ah included, Carbon fiber split shaft, Pivoting head for vertical edging and Brushless motor.

What are the best alternatives to the EGO Power+ ST1521S 15-Inch String Trimmer?

Worth comparing: Worx WG183 40V String Trimmer, Greenworks 40V 12-Inch Cordless String Trimmer and Husqvarna 128LD Gas String Trimmer. Each ranks near it in our research for a slightly different buyer.

Where can I buy the EGO Power+ ST1521S 15-Inch String Trimmer?

It's sold on Amazon. Prices and stock change often, so check the current listing before you buy, our link takes you straight to it.

What makes a string trimmer good for edging, versus just trimming?

A trimmer built for edging needs a head that pivots 90 degrees so the line spins vertically instead of horizontally. Look for a tool-free pivot mechanism, a guide wheel or edging guard that keeps the cutting line at a consistent depth along a walkway, and a straight or split shaft that lets you hold the head at the right angle without bending over. Models like the EGO ST1521S and Worx WG183 both include a pivoting head, which is the single biggest factor separating a trimmer that edges well from one that only cuts flat.

Can any string trimmer be used as an edger?

Most modern trimmers with a pivoting head can edge reasonably well, but a dedicated edger attachment or a wheeled edger still cuts a straighter, cleaner line for long driveway runs. A pivoting-head trimmer is the better choice for occasional edging around beds, patios, and curves where a rigid wheeled edger can't follow the contour.

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