Review: Leatherman by the Numbers #4


Review: Leatherman by the Numbers #4

Once upon a time, a long while ago, there was a single man standing at a grinder spitting out ones and twos of brilliantly design One Piece Multitools (OPMTs). They were perfect for popping a brew or as an ad hoc screwdriver. They were made of premium materials with wonderful, hand crafted touches. That man was Peter Atwood and his tools, Atwoods, have become catnip to a certain group of people.

It was only a matter of time until big companies (and high end custom knife makers) got in on the game. The business of these tools provides ample incentive–they have no moving parts, very few grinds, and aren’t terribly complicated to make, compared to say, a folding flipper knife. No detent to get just right, no edge to carefully grind. And so, as markets this imbalanced are wont to do, the one-piece multitool (OPMT) market exploded.

In the three years I have been covering EDC gear, the number of OPMT makers and designs has increased at an exponential rate. Big companies can laser or water jet sheets full of these tools, basically printing money. And custom makers that are used to the fidgety precise work of hand made knives, can bang out a dozen or so and sell them for $50-$100 in the blink of an eye. Profit is everywhere.

But creative designs are not everywhere. The market has become stagnant and very few innovations are coming to the forefront. Tool after tool is either a cleverly named animal in silhouette or a take off on one of Peter’s original designs. There are guys doing their own thing, like TT PockeTTools, but by in large this is a market niche stuffed to the gills with me-too designs. So when Leatherman announced a series of new OPMTs (some of which have more than one piece), it was an interesting move. Leatherman bought out Piranha tools a while ago and released their designs under the Leatherman name, but this new series of tools, called By the Numbers, is the first set of tools design by Leatherman and intended for EDC (they made a few specialized tools for snowboarding and the like before the By the Numbers series).

One member of the new line really caught my eye: Leatherman #4. This is a review of this cleverly design tool.


The Leatherman #4 is a keychain sized multitool.

It is technically not a one piece multitool as it has a driver bit suspended in a rubber insert in the middle of the tool. The bit and the tool itself are made of 420 series stainless steel. The specs do not state if it is 420HC or 420J, the two likeliest candidates. In this role the differences between the two don’t really matter. Both are very good at resisting corrosion.

The #4 has five tools (though the product page lists only four): the ubiquitous scraper/pry, the Phillips driver, the flathead driver, the box cutter, and the bottle opener. The bit driver is a 2D Phillips driver on one end (a #1 and #2) and a 3/16″ flathead driver on the other end.


On the side of the tool opposite the bottle opener there is a long, cantilevered piece of steel. It functions as a spring arm that holds the bit driver in place when in use. When not in use the bit driver resides in a thick piece of rubber in the middle of tool.


The overall design of the #4 is something of a break from past designs. The spring arm on top of the tool is very unique. The complement of tools is nothing ground breaking, but how they all work together is quite different. The pry/scraper is pretty much standard in the OPMT market, so that’s not the quirk.


The bit retention device is clever and the bottle opener is also a bit outside the norm.


I carried the #4 with me for about a month, and I used it for some light home improvements. Carrying the tool with me for a month meant that it was used about 60 times as a bottle opener (I helped friends…don’t be so judge-y), 10 times as a box cutter, and 5 times as a driver. One thing that is especially nice about the #4 is that because of the spring arm and how secure the bit is in the using position, you can do some really fastener driving with it. Additionally, because of the overall compact dimensions, it can get into spaces that even stubby screwdrivers can’t.


As I mentioned above, every single design feature that is unique really works. This isn’t a tool that’s different to be different. It has a few new ideas and all of them are good.

I cannot emphasize enough how nice the spring arm is. By locking the bit driver into place, it lets the #4 transcend the competition. Most of the time the drivers on these tools are pretty low torque, low utility designs, but here, I did some real fastener driving. Over time, I have become less enamored with these tools because their designs seemed to necessitate a less useful tool (how much torque can you really generate from one of those box wrench designs?). The #4 fixes that to a degree. I don’t want to oversell this; it’s not a real screwdriver, but it is a substantial step up from the field.

The rest of the tools are good to great. The scraper is narrow and lacks a v-notch, but it still works. The box cutter good, and the bottle opener is quite nice once you get used to it.  But the spring arm/driver is the star here.



At $13, the #4 is about 1,000 times the value proposition of, say, the RUT, a tool of the same class from uber custom maker Todd Rexford. It works well, it has real bit drivers, and it is quite small. The materials are fine for the application and the overall design is unique. As a companion on your keychain, you can do a whole lot worse. I am not sure if it is better than the Gerber Shard, but that is high praise as the Shard is probably the best tool available, regardless of price, from a pure utility point of view.

Now can we just be honest and call it like it is. This isn’t the #4, it’s the Sea Horse:


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A devoted Dad and Husband, daily defender of the Constitution, and passionate Gear Geek. You can find Tony's reviews at his site:, on Twitter at EverydayComment, on Instagram at EverydayCommentary, and once every two weeks a on a podcast, Gear Geeks Live, with Andrew from Edge Observer.

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