After we wrapped up our testing, we had no question that the Bosch PS31-2A 12-Volt Max Drill/Driver Kit offers the best performance for around-the-house work. It’s not only the lightest and most compact drill we got our hands on, but during both tests it also stood head and shoulders (and chest and waist) above the rest. In the battery-life category, the Bosch PS31-2A really had no competition among the other 12-volt drills we looked at. During the screw test, the other drills all managed between 70 and 90 screws on a single battery charge. The Bosch PS31-2A drove 138 screws—over 50 percent more than the second-place drill, the Milwaukee 2407-22. As for power, the PS31-2A drove screws evenly and without issue, even through tough knots. The majority of ther 12-volts often had issues fully sinking the screws heads flush with the wood.
The drilling test yielded similar results with the PS31-2A far ahead of the pack. While the other five 12-volts bored between eight and 12 holes, the PS31-2A drilled 25, two to three times more than the other drills. This wasn’t an easy task for any of the 12-volts, and they all had to fight their way through the process with significant amounts of stalling and binding, but the Bosch worked through it all and just kept on going and going.
In both of these tests, the 12-volt PS31-2A actually achieved higher numbers than many of the larger 18-volts that we tested. It drove more screws than seven of them and drilled more holes than four. We need to emphasize that these drills aren’t even in the same class, so this is like a middleweight scoring punches on a heavyweight. The smaller PS31-2A took quite a bit longer to do these tasks, but these impressive numbers still display the overall abilities of the tool.
What’s significant about the Bosch PS31-2A is that this mega power and endurance doesn’t come in a bulky package. In addition to being the most powerful 12-volt, the PS31-2A is also the smallest and lightest drill we tested. Most of this size reduction is where it really matters—in the main body of the tool. Though the handle is big enough for my large hands to grip comfortably, the total length of the drill, nose to tail, is barely 6¾ inches. All of the other 12-volts are 7 inches or longer, with the Craftsman the biggest at 7¾ inches.
With this small size, it’s no surprise that the PS31-2A is also very light, weighing only 2 pounds, 2 ounces (with a battery). The Black+Decker and the Craftsman are both just a whisker heavier at 2 pounds, 3 ounces. The rest are at least 2 pounds, 6 ounces, with the Milwaukee as the heaviest at 2 pounds, 10 ounces. The good news is that though the PS31-2A is lightweight, it feels very solid, not cheap and plasticky. It feels durable and it didn’t even flinch the few times I accidentally knocked it off the table.
During unstructured testing is when the PS31-2A’s diminutive size really came in handy. It’s such a small, light, easy-to-handle tool that my afternoon spent hanging window blinds above my head was no problem at all. The size was also beneficial as I reconfigured some drawer slides in a cramped kitchen cabinet. I also had to unscrew a ceiling access panel that had a built-in bookshelf directly underneath it. With the extremely tight clearance, the Bosch PS31-2A was the only drill that could fit in the space and remove the screws.
For additional features, the PS31-2A has a battery-life indicator. This consists of three lights on the side of the tool that light up accordingly any time the drill is activated. The design of the lights is nice because once the tool is activated, it’s easy to check the battery life with a simple glance. On many of the other drills, namely the 18-volts, a button needs to be pressed to get the indicator lights to activate. This requires stopping what you’re doing.
Another benefit to the Bosch PS31-2A is that it is part of an expansive battery platform. Bosch offers many other tools, from saws to radios to oscillating tools and even heated jackets, that run off the same 12-volt battery. With the PS31-2A (and its two batteries) in hand, these additional items can all be purchased “bare tool,” meaning, without the battery. Depending on the tool, this can save anywhere from $40 to $60, making this an economical approach to expanding a tool collection.
The PS31-2A has received praise from many reviewers. Stuart Deutsch of ToolGuyd writes that the PS31 “can handle many if not most of the jobs 18V drills and drivers are used for.” He continues, “It lacks the mass, size, and power to be used in high-torque or heavy duty applications, but it plows through smaller holes and can be used for most screwdriving applications as well.” He wraps up his review calling the PS31, “highly recommended.”
Much of the same sentiment can be found in Clint DeBoer’s review of the PS31-2A at Pro Tool Reviews. He tested the PS31-2A by driving 3-inch screws into a pressure-treated 4-by-4. He drove 51 screws (before running out), then removed 45 of them. As DeBoer writes that’s “a very respectable amount of work.” He “also felt that the Bosch Drill/Driver didn’t seem to be very finicky about knots or whether the PT wood was soft or hard—it just drove screws. This tool can do some heavy-duty work.”
DeBoer also installed a lock set with the PS31-2A, which requires the use of a hole saw (an item for cutting wide-diameter holes). Even though this took longer than it would with an 18-volt drill, he notes that, “It was good to know that a reasonable amount of heavy-duty work could be expected from this tool, but that it also sufficed for smaller jobs where a full-size tool is simply overkill and cumbersome.”
In a couple of other reviews that directly compared the Bosch PS31-2A with other 12-volts, it didn’t do so well, but for a reason. The roundups at This Old House and Popular Mechanics date from 2010/2011 and used the original version of the PS31-2A, which came with an older version of its 12-volt battery. Purchasing the items today, it comes with an updated battery that offers longer run time and additional power.
The PS31-2A is sold in a few different packages. The simplest (and least expensive) is with two batteries and a zippered soft case, which is what we recommend. It’s also currently available with a Bosch L-BOXX (part of Bosch’s modular click-together storage system) or bundled with a cordless radio and a Bosch L-BOXX. Lastly, the PS31-2A can be bundled with Bosch’s PS41 12-volt impact driver.