Milwaukee M18 Fuel Sawzall with One-Key Review | 2721-22

Milwaukee M18 Fuel Sawzall with One-Key
PTR Review
  • Cutting Speed 9.1
  • Vibration Control 9.3
  • Feature Set 8.5
  • Size 6.6
  • Value 7.8

If Milwaukee One-Key technology makes sense to you from both a tool tracking and performance standpoint, then there's no reason to think twice about adding the One-Key Sawzall to your inventory.

Overall Score 8.5 (out of 10)

Back in 1951, Milwaukee Tool invented the first electric hacksaw that would be able to saw through anything and hence named it the Sawzall. A lot has changed in the past several decades, but the concept is still the same – use electrical power to move the blade back and forth quickly and replace the need to saw anything by hand. One of the most advanced in reciprocating saw technology is the 2721 Milwaukee M18 Fuel Sawzall with One-Key.

The humble Sawzall may not seem the most likely candidate to receive One-Key technology from Milwaukee. However, Milwaukee had some compelling reasons to do so that we’re going to go into in just a minute. We initially saw the Milwaukee M18 Fuel Sawzall with One-Key at Milwaukee’s New Product Symposium this past summer and were able to bring you some first impressions along with some practical application in a video that you can see here.

Editor’s note: this review originally published in January 2017. It has been updated with results from our head-to-head review.


  • Only reciprocating saw with smart controls currently available
  • Excellent cutting speed across all materials
  • Excellent vibration control
  • Compact size


  • No orbital action
  • One of the heaviest in its class

First Impressions

It’s no secret that Milwaukee builds a tough, durable tool and the Milwaukee M18 Fuel Sawzall with One-Key is certainly no exception. It’s jobsite tough without compromise and lives up to the NBHD reputation Milwaukee thrives on.

The feature set is a curious mix, highlighted by One-Key. One-Key does more than just tool tracking for the M18 Fuel Sawzall – it brings it an entirely new identity. When it comes to woodcutting, there’s no real change. Pop your Milwaukee Ax blade in Mode 4 for high speed and cut away. Metal cutting is where the technology really comes into play.

Within the One-Key app, you can choose the blade you’re using with the material you’re cutting and the software will select the best settings for that application. Those settings include how fast the blade will move and whether or not to include a soft start.


What makes the feature set curious is that we get the top technology available but there’s no orbital action mode on the saw – a feature that’s nowhere near new.

Working around the saw, we find a host of standard features. The shoe is adjustable without the need for any tools, you have a standard lockout switch, and there’s a rafter hook.

Milwaukee M18 Fuel Sawzall with One-Key

The blade lock is down on the left side of the tool and is tool-free, but is a slightly different design than the lever-action found on most saws that use a similar mechanism. Milwaukee calls this their Quik-Lok system and it is more concealed than most. The mechanism is spring-loaded and snaps back into place when you let your finger off of. I found it to be a little tougher to use than a standard lever, yet extremely confident in its locking.

Milwaukee M18 Fuel Sawzall with One-Key


The first thing you notice about almost any tool when you pick it up is the weight. The Milwaukee M18 Fuel Sawzall with One-Key is fairly heavy, weighing in at just over 7.5 pounds bare. We originally tested it using Milwaukee’s 9.0 amp hour battery which boosted the weight up to almost 10 pounds. However, we like this model best with the 5.0Ah battery, bringing the weight down to a more manageable 9.2 pounds.

While that’s still pretty heavy, cordless Super Saws with their advanced power designs are heavier across the board.

The Milwaukee 2721 is one of the more compact saws in the standard 18V class. It’s just 17.4 inches long with the shoe all the way in. The shortest is 17.1 inches and the longest is a whopping 19.5 inches, putting Milwaukee very close to the top of the compact side.

Handle ergonomics are on par for the course. It’s actually tough to make the reciprocating saw that has what I would consider comfortable handle ergonomics. Both the D-handle and upper housing handle are fairly standard in shape for this class with some contour to the D-handle. The rubber overmold helps with grip and to dampen the vibration slightly.

Milwaukee M18 Fuel Sawzall with One-Key


In our nail-embedded wood-cutting test, this Milwaukee cordless Sawzall posted a solid 11.02-second average. Finishing nearly 2 seconds behind the leader (Makita XRJ05, 9.09 seconds), it’s still well ahead of the slowest saws in its group.

Compared to its big brother—the M18 Fuel Super Sawzall—the gap is more significant. That model averaged 6.67 seconds and was the third-fastest of all 40+ models we tested, including corded saws.

Milwaukee M18 Fuel Sawzall with One-Key

The Milwaukee M18 Fuel Sawzall with One-Key continued to perform well in our metal cutting tests. In 2-inch EMT, it needed just 3.75 seconds on average, beating out every other reciprocating saw in its class.

Moving from thin-wall pipe to solid stock, it took an average of 9.68 seconds to cut through #5 rebar. Kobalt’s 24V reciprocating saw was the fastest here, needing just 7.58 seconds. However, Milwaukee again proves it’s no slowpoke, finishing well ahead of the bottom time of 14.18 seconds.

When you look at your options, the Milwaukee 2721 in one of only a few reciprocating saws that have consistently high cutting speeds across varying materials. One-Key is a big help there. If you’re willing to take the time to punch in the information, you’ll cut faster and use fewer blades.

Vibration Control

Milwaukee doesn’t tout a particular vibration control technology as some brands do. However, this design is still excellent in that department. After our 3-man testing team, each took a turn with all the reciprocating saws in the class, we averaged our scores to get a final ranking. Milwaukee earned 93 points for vibration control, second only to the Bosch GSA18V-125.


You’ll pay a premium to have the added technology on top of one of the industry’s top saws. The bare tool costs $229 and the kit with two 9.0Ah batteries is $469.

That’s certainly not chump change, but going ahead with the higher capacity battery opens up other options for you like grabbing the M18 Fuel Miter Saw.

If the whole One-Key thing isn’t for you, pick up the 2720 model. It’s the same saw without One-Key and runs about $50 less.

Milwaukee’s bare tool price is in line with most of the premium brands. The kit price is a bit more, but several other brands are keeping the price lower by only giving you one battery.

The Bottom Line

There’s no doubt that the Milwaukee M18 Fuel Sawzall with One-Key is a Pro-level tool. The fact that there’s no orbital action is offset by the realization that no one else except for Ridgid has orbital action on their top cordless recip saws either. If Milwaukee One-Key technology makes sense to you from both a tool tracking and performance standpoint, then there’s no reason to think twice about adding the One-Key Sawzall to your inventory.

Milwaukee M18 Fuel Sawzall with One-Key Features

  • Milwaukee One-Key Enabled
  • 4 Customizable Cutting Modes
  • Quik-Lok Concealed Tool-Free Blade Clamp
  • Tool-Free Adjustable Shoe
  • LED Work Light

Milwaukee M18 Fuel Sawzall with One-Key Specifications

  • Model: Milwaukee 2721-20
  • Voltage: 18V
  • Power source: Milwaukee M18 RedLithium battery packs
  • Stroke length: 1-1/8″
  • No Load Speed: 0 – 3,000
  • Orbital Action: No
  • Vibration Control: No
  • Weight (Bare): 7.54 pounds
  • Weight (With 9.0 Ah Battery): 9.94 pounds
  • Warranty: 5 years
  • Price: $229 (bare), $469 (9.0Ah kit)

Related articles