Stanley FatMax Auto-Retract Safety Knife Review

Stanley Retractable Utility Knives

I would not say that a major part of the job description around the PTR offices revolves around cutting into boxes and plastic, yet we do a fair amount of it. We do happen to receive a lot of packages in the mail, and we’ve found that having knives handy comes in, well, handy. Undoubtedly, plenty of you out there work in fields that require the use of boxcutters or knives even more than we use them. Cut safety also seems to be a huge area of concern for OSHA for some reason. Stanley is meeting the needs of new OSHA regulations with the FatMax Auto-Retract utility knife.


Editor’s Note: Check out our best utility knife article for our top picks in this category.

Don’t Cut Yourself

Most people won’t choose to use auto-retracting utility knives unless they have to. They’re a pain. However, sometimes company policy and government regulation take the choice away from you. When that happens, the design of a retractable utility knife makes all the difference.

Common Features

Auto retraction allows you to start your cut and release the blade extension mechanism while the pressure of the material against the blade keeps it extended. Once that pressure releases, the blade automatically retracts back into the housing. It works whether you keep the handle/slide pressed or not. When you have the handle or slide engaged, you’ll need to release it and then re-engage it to get the blade back out.

Working around some materials, like auto glass, make it impossible to simply make a nice, long cut in one motion. Those are the kind of jobs where different blade engagement designs start to separate more decisively.

Both Stanley retractable utility knife models come with a trapezoidal round-point utility blade. These blades have the tips rounded off to prevent accidental stabbing. While it’s possible to replace them with a standard trapezoidal blade, you’ll likely be out of compliance if your workplace requires a safety utility knife.

Stanley Retractable Utility Knife

Blade changes require a little dexterity. You need to push the blade into the open position and press the red blade release button while pulling out the old blade or inserting the new one. Getting them out is easy enough, but getting the new one in can take a little wiggling to find the right spot. You’ll also notice play in the blade when it’s installed, but that’s the nature of a trapezoidal system that uses tabs to hold the blade in place.

Both knives are reasonably comfortable in hand. I don’t mind the additional width as it fills my hand well and helps with a secure grip.

Squeeze Handle or Top Slide?

Stanley FatMax FMHT10370

The squeeze handle Stanley FatMax safety knife offers all the safety features you need. Like all safety utility knives, the blade uses a spring to auto retract and there’s no button to lock the blade in the open position. The long handle trigger doesn’t require tons of pressure and it encourages a pretty natural grip.

When you have to have a safety knife due to policy, keeping the blade out on this model is much easier than the thumb slide model. It also opens up the possibility of a reverse grip if you’re working on a material that’s easier to cut by pushing away from your body.

Stanley also includes a blade lock. Sliding the button into the locked position will prohibit you from engaging the blade. Take note that, while you’re able to lock yourself out from using the knife, you can’t lock the blade in the cutting position. Just behind the lock is a lanyard hole for when you need to tether the knife.

Stanley Retractable Utility Knife

Stanley FatMax Safety Knife Squeeze Handle Features

Stanley Retractable Utility Knife
  • Pressure-sensitive blade automatically retracts once disengaged from cutting surface.
  • Easy trigger squeeze technology exposes the blade and helps reduce user strain.
  • Blade lock helps prevent accidental blade exposure.
  • Metal body with slip-resistant bi-material grip for durability and control.
  • Quick, tool-less blade change.
  • Accepts standard round-point utility blades.
  • Lanyard hang hole for easy transportation and storage.

Stanley FatMax Safety Knife Squeeze Handle Specs

  • Model Number: Stanley FatMax FMHT10370
  • Number of Blades: 1
  • Length: 6-1/5″
  • Safety Knife Type: Auto-Retracting Blade
  • Includes Premium Auto-Retract Squeeze Safety Knife, Round-Point Utility Blade
  • Warranty: Lifetime Limited
  • Price: TBA

Stanley FatMax 10367

With the same safety intent behind the design, there’s a second option if you want a solidly built Stanley FatMax safety knife. This one has a thumb-slide for blade extension. Like I mentioned earlier, this style doesn’t seem as natural to use since your thumb is forced into service pushing the blade out. It also means you can’t use a reverse grip.

Stanley Retractable Utility Knives

This model also has a lock on it and includes three levels of blade exposure integrated into the same mechanism. Some users will like it, others prefer full extension all the time. It’s up to you.

Stanley Retractable Utility Knives

Unlike the handle trigger model, this model has additional blade storage. Lifting up the overmold from the back of the body, you’ll find storage for three extra blades.  A lanyard hole for tethering is at the back as well.

Stanley FatMax Safety Knife Tri-Slide Features

  • Pressure-sensitive blade automatically retracts once disengaged from cutting surface.
  • Oversized, contoured tri-slide button can be engaged from three positions (top, left, and right side).
  • Three blade depth settings limit blade exposure and help protect contents.
  • Blade lock helps prevent accidental blade exposure.
  • Metal body with ergonomic, slip-resistant bi-material grip for durability, comfort, and control.
  • Quick, toolless blade change.
  • Accepts standard round-point utility blades.
  • Integrated blade storage in handle.
  • Lanyard hang hole for easy transportation and storage.

Stanley FatMax Safety Knife Tri-Slide Specs

  • Model: Stanley FatMax FMHT10367
  • Number of Blades: 4
  • Length: 7″
  • Safety Knife Type: Auto-Retracting Blade
  • Includes Premium Auto-Retract Tri-Slide Safety Knife, 4 Round-Point Utility Blades
  • Warranty: Lifetime Limited
  • Price: $28.48

Final Thoughts

Stanley Retractable Utility Knives

There’s no real hiding that I’m not a fan of safety utility knives. It just seems like I’m being treated like a child when it’s forced on me. But that’s the culture we live in. Without diving into the whole “personal responsibility” discussion, these Stanley FatMax safety knife models have a pretty solid construction with their metal housing and rubber overmolds.

If it were possible, I’d combine the features of the two styles. I definitely prefer working with the squeeze style, but I like the convenience of extra blade storage on the thumb slide design.

If you’re not a professional that needs a safety utility knife, I’d point you towards something more like an OLFA breakaway style. However, if you’re required to use one on the jobsite, Stanley makes a pretty compelling product with these metal designs that reach into the Pro market. If you’re more prone to losing your utility knife or just like the idea of a safety style at a lower price point, there’s also a plastic model available.

Related articles