Flex 24V Brushless Impact Driver Offers Compact Design and Extra Power
There are two impact drivers to choose from for the Flex 24V cordless tools at Lowe's and other retailers. Our review today is the Flex 24V Brushless Impact Driver with Quick Eject. It's the higher-performance and more feature-rich of the two, though the standard brushless shock driver isn't worth shaking out.
advantage
- Monster 2500 in-lbs torque
- Excellent performance in demanding applications
- 3 standard speeds plus 2 self-tapping screw modes
- Quick Eject chuck opens chuck without taking hands off handle
- Register before 12/31/22 for a lifetime warranty
shortcoming
- heavy for its size
Flex 24V Brushless Impact Driver Performance
Flex takes performance farther than its competition with this brushless model. With a top speed of 4000 RPM, it can develop 2500 in-lbs of torque. It's class-leading speed combined with class-leading power.
To help you control performance, you can use three standard patterns and two self-tapping screw patterns. Between all of these, you should be able to find the right mix of speed and force for most fastening jobs.

To see how the Flex dials in all of this, we put it to the RSS test to see how it handles large structural fasteners. Using 8" RSS screws from GRK Fasteners, we drove into the layered OSB subfloor. No, it's not a "normal" application, but OSB is really consistent, so it's good material when you compare tools the way we do.

The Flex finished with a 5-test average of 6.13 seconds. Of the impact drivers we've tested so far, only Milwaukee's Gen 3 M18 Fuel has a faster time (5.84 seconds). On top of that, the third-place finisher was more than a second slower.
We also wanted to test it on our Inertia Torque impact torque tester. However, the force behind the hammer and anvil was so great that it snapped our 1/2" square adapter as if it were made of plastic.
Flex 24V Brushless Impact Driver Design Notes
size and weight
Looking at the tool, it's clearly compact. It measures 4.75 inches from front to back. It's a bit wider than some of its premium competition, as it's exactly 2.5 inches wide.

For size, the tool feels a little heavier than we're used to. It weighs 2.8 pounds bare-bones, 4.1 pounds with a 2.5Ah battery, and 4.9 pounds with a 5.0Ah battery pack. Some of that weight comes from using a 6-cell battery system instead of a 5-cell system like the 18V and 20V Max tools.
The other part is the building itself. The shock driver feels like its weight has more to do with its quality build than anything else. With a 2.5Ah battery, it's very well balanced, which is the battery pack we prefer to use.
Handle ergonomics
Flex took some time to think about their handle ergonomics and it shows. The foundation has a nice curve and fits nicely in your hands, similar to what DeWalt and Metabo HPT do. From a textural standpoint, overmolded coverings are pretty aggressive. It helps wick away sweat and gives you a better grip when your hands get a little greasy.

Quick eject chuck
While there's no one-handed bit insertion or active spring ejection, the Flex 24V Brushless Impact Driver introduces a quick ejection feature. Above the trigger, there is a button that you press with your finger to push the collet forward to the open position.

You don't have to move your hands from the handle to the switch bit, which makes it a much more convenient way to manage. It is especially useful when you are working at heights or in places where tools are not easily accessible.
Additional features
- Foot-operated LED lights
- Belt hook (left side mount only)
- Bright and eye-catching 4-LED charging indicators on both sides of the battery
You can get the Flex 24V Brushless Impact Driver with Quick Eject a few different ways. As a bare tool, it's priced at $159.00. There are several kits and combos that are also a part of this. Here's the breakdown:
- Kit with 2.5Ah and 5.0Ah batteries (FX1371A-2B): $229.00
- Kit with 6.0Ah Stacked Lithium Battery (FX1371A-1H): $279.00
- Impact Drill and Impact Driver Lithium Stack Combo (FXM202-2G): $499.00
- Hammer, Impact Driver, Circular Saw, LED Light Stackable Lithium-Battery Combo (FXM403-2G): $649.00
The standard warranty period for both batteries and tools is 5 years. However, if you register your tools, batteries and chargers by December 31, 2022, you will receive a lifetime warranty on all of them under the Flex Founders program.
the bottom line
We've all wondered where the Flex fits among the other cordless impact drivers on the market today. After running it through our tests and taking a closer look at its design, it's clear that the Flex 24V Brushless Impact Driver with Quick Eject is of the premium professional grade. In our experience, Flex is legit, and the traditional powerhouses have some serious competition to consider.
Flex 24V Brushless Impact Driver Specifications
- Model: Flextronics FX1371A
- Power: Flex 24V battery
- No-load speed: 4000 RPM max
- Maximum Torque: 2500 in-lbs
- Impact rate: 4450 IPM
- Length: 4.75 inches
- Weight: 2.8 lbs bare, 4.1 lbs at 2.5Ah, 4.9 lbs at 5.0Ah
- Warranty: Tool and battery 5 years (useful life after registration 12/31/22)