Flex 24V Mid-Torque Impact Wrench Review FX1451-1C

Flex Mid-Torque Impact Wrench

Flex 24V Mid-Torque Impact Wrench Is Smaller and Lighter, But Still Packs a Serious Punch

A few years ago, we got our hands on the Flex 1/2-Inch High Torque Impact Wrench that offered some serious muscle for demanding situations. However, high-torque impact wrenches aren’t always suitable when working with delicate materials, such as cast steel. It’s just as Uncle Ben told Peter Parker, “With great power, comes great responsibility”. So today, we’re taking a close-up look at the Flex 24V Mid-Torque Impact Wrench that offers a solid blend of speed, power, and finesse to boot.

Check out our Best Cordless Impact Wrench recommendations!

Flex Mid-Torque Impact Wrench Performance

Flex Mid-Torque Impact Wrench
  • No-Load Speed: 0-450/1600/2700 RPMs
  • Max Breakaway Torque: 750 ft-lbs.
  • Max Fastening Torque: 600 ft-lbs.
  • Impact Rate: 3100 IPM

The Flex Mid-Torque Impact Wrench packs a pretty serious power into its compact frame. The FX1451’s brushless motor delivers 600 ft-lbs of fastening torque, up to 750 ft-lbs of breakaway torque, and a max impact rate of 3,100 IPM. Flex designed this impact wrench with three main speed modes that range from 450 RPMs up to a blazing fast 2,700 RPMs.

Flex Mid-Torque Impact Wrench

When used in for automotive applications, Flex’s Auto mode serves two purposes. First, it offers more control while removing nuts and bolts by sensing when they’ve broken loose and stopping rotation. Second, the Auto Stop mode helps prevent over-tightening, breaking, or stripping threads by stopping rotation about 1-second after it begins to impact.

As we mentioned before, on paper, this impact wrench boasts an impressive amount of power. In fact, they are among the best we’ve seen from the mid-torque class.

Using our Inertia Torque L-1000 impact torque tester, it produced a consistent 414.8 ft-lbs working torque using a 3.5Ah Stacked Lithium battery. For some added perspective about Flex’s battery technology, we measured 387.9 ft-lbs of fastening torque using a 5.0Ah battery in the same test.

L1000 Torque Testing

Keep in mind, working torque measured by the L-1000 is lower than the maximum torque measured by testing methods for manufacturer specifications. This is normal and a better representation of how much force you’re applying to each fastener.

Of the mid-torque impact wrenches we’ve tested on this machine so far, Flex is on the high end of the scale. It’s not the highest—that belongs to the Metabo HPT 36V model at the moment. However, we have some head-to-head testing planned that will cover the full range of mid-torque, so keep your eyes open on our YouTube channel for those test results.

Flex Mid-Torque Impact Wrench Design Notes

Flex Profile
  • Model: Flex FX1451
  • Power Source: Flex 24V battery
  • Anvil: 1/2 in. Friction Ring
  • Weight: 4.3 lbs. (bare), 5.9 lbs. (with 3.5Ah Stacked Lithium battery), 6.6 lbs. (with 5.0Ah battery)

The Flex FX1451 clocks in at 4.3 pounds as a bare tool, 5.9 pounds with a 3.5Ah Stacked Lithium battery, and 6.6 pounds with a 5.0Ah battery. This is significantly lighter than the high-torque FX1471, but still a little on the heavy side for a mid-torque. Regardless, this tool is very well-balanced considering its size.

Flex anvil

To help reduce vibration, Flex utilizes a small isolation zone between the motor housing and the handle, making it very comfortable to use. Additionally, the grip is draped in a textured rubber overmold that provides a little extra insulation for your hands.

Additional Features

  • LED Work light
  • Two-position belt hook
  • Compatible with all Flex 24V batteries

Flex Mid-Torque Impact Wrench Price

The Flex 24V Mid-Torque Impact Wrench is available in a few different configurations with a few different price points. As a bare tool, the FX1451 retails for $199.99 and for $269.99 they add in a 5.0Ah battery, charger, and storage bag. Flex also offers an upgraded battery kit option that comes with a 3.5Ah Stacked Lithium battery and a hard shell storage case. No matter which one you choose, it’s all protected by the Flex Founder’s Limited Lifetime Warranty when registered within 30 days of purchase.

The Bottom Line

The Flex 24V 1/2-Inch Mid-Torque Impact Wrench has you covered when it comes to tackling a full range of automotive and high-demand fastening tasks. After considering the overall feature set, performance specs, and the available kit options, we believe it’s an excellent option for serious DIYers and Pros, alike.

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