When Flex introduced the 24V Quick-Eject Impact Driver to the professional tool market a few years ago, it made an immediate splash. Combining relentless high-voltage power with innovative features, it challenged the status quo dominated by long-established industry giants. Now, the company is rolling out its next generation of flagship 24V tools, led by the newly minted Flex 24V One-Touch Impact Driver (FX1372).
At first glance, the FX1372 bears a striking resemblance to its predecessor, the FX1371. However, a closer inspection under the hood and on the jobsite reveals that Flex has implemented calculated, highly practical engineering updates. To evaluate whether these modifications translate to meaningful real-world gains, we put the FX1372 through our rigorous, standardized testing protocols, measuring it against its predecessor and the fiercest heavy-hitters in the professional cordless marketplace.
Main Facts: What You Need to Know About the FX1372
The Flex FX1372 represents a philosophy of methodical refinement rather than a desperate reinvention. Retaining the core DNA that made the previous generation a top contender, the new model introduces a more compact frame, a lighter footprint, and an overhauled bit-ejection mechanism.
- Motor Type: Brushless
- Max Speed: 4,100 RPM
- Max Impact Rate: 4,550 IPM
- Max Torque: 2,500 in-lbs
- Bare Tool Weight: 2.4 lbs (down from 2.8 lbs on the FX1371)
- Kit Weight (with 5.0Ah Battery): 4.6 lbs (down from 4.9 lbs)
- Head Length: 4.40 inches (shorter than the predecessor’s 4.75 inches)
- Retail Price: $299 (includes two 5.0Ah batteries, a charger, and a hard-shell storage case)
- Warranty: 3-year standard warranty, upgradeable to 5 years upon registration within 30 days of purchase.
Chronology of the 24V Flagship Evolution
To understand where the FX1372 fits in the market, it is essential to look at how Flex has iterated on its high-performance line.
The Foundation: The FX1371 Era
When the original Quick-Eject impact driver dropped, its defining characteristic was the innovative collet system designed to speed up workflow. Powered by a robust 24V brushless motor, it quickly climbed to the top of historical performance charts for raw driving speed and impact rate, cementing Flex as a legitimate alternative to the "Big Three" Pro brands (Milwaukee, DeWalt, and Makita). Despite its raw power, users noted that the tool carried a slightly larger physical footprint and heavier weight than some minimalist competitors.
The Next Generation: The FX1372 Launch
Recognizing both the successes and minor critiques of the first-generation flagship, Flex engineers went back to the drawing board. Rather than overhauling a motor system that was already leading the category, they focused on slimming down the chassis, improving weight distribution, and upgrading the user interface—specifically the collet. The result is the FX1372, designed to maintain peak performance metrics while offering superior handling in confined workspaces.
Performance and Supporting Data
The ultimate test for any professional impact driver is how it handles heavy fasteners under pressure. We subjected the FX1372 to our standardized speed and torque evaluations, utilizing a kitted 5.0Ah battery to replicate real-world jobsite conditions.
Power and Speed Metrics
At the heart of the FX1372 is an advanced brushless motor. It churns out up to 4,100 RPM, 4,550 IPM, and a massive 2,500 in-lbs of torque. When looking at historical data across the professional marketplace, these specifications place the FX1372 firmly at the top tier of the speed and impact-rate category.
The tool features a 3-speed transmission:
- Mode 1: 1,500 RPM (for delicate fastening)
- Mode 2: 2,000 RPM (for controlled driving)
- Mode 3: 4,100 RPM (for maximum speed and power)
Additionally, Flex integrated two specialized self-tapping modes designed to maximize control when driving fasteners into thin (T1) or thick (T2) sheet metal, minimizing the risk of stripping or over-driving.
Standardized Testing Results
1. Heavy-Duty Screw Driving Test
In our standardized structural screw test, the FX1372 completed the course with an average time of 5.84 seconds per screw.
- FX1371 (Predecessor): 5.86 seconds
- Milwaukee M18 Fuel (2953): 5.96 seconds
- DeWalt 20V Max XR (DCF860): 7.54 seconds
- Makita 40V XGT (GDT01): 13.11 seconds
While the performance numbers are virtually identical to its predecessor—which is unsurprising given that raw motor output remained largely consistent—the FX1372 comfortably maintains its crown, outperforming major competitors in raw driving speed.
2. Bolt Break Test
Evaluating the tool’s immediate torque delivery and impact efficiency, the FX1372 averaged 1.74 seconds per nut during our bolt break evaluation.
- FX1371: 1.75 seconds
- Milwaukee M18 Fuel: 1.54 seconds
- Ridgid 18V (R862312): 1.93 seconds
- DeWalt 20V Max XR: 2.56 seconds
- Makita 40V XGT: 2.80 seconds
Along with Milwaukee and Ridgid, Flex remains one of the exclusive mainstream professional brands capable of breaking the 2-second barrier in this grueling test, establishing a healthy performance gap over DeWalt and Makita.
Design Evolution: Ergonomics and the One-Touch Collet
While performance metrics remained stable, Flex engineers directed their primary modernization efforts toward ergonomics and user interaction points.
Shorter, Lighter, and Better Balanced
- Bare Weight: 2.4 lbs (A 0.4 lb reduction from the 2.8 lb FX1371)
- Kit Weight: 4.6 lbs with a 5.0Ah battery (Down from 4.9 lbs)
- Head Length: 4.40 inches (A significant 0.35-inch reduction from the previous 4.75 inches)
The reduced head length is a game-changer for tradespeople working in cramped environments, such as between floor joists or inside cabinetry. Even when paired with the substantial 5.0Ah battery, the tool maintains an exceptional center of gravity, mitigating wrist fatigue over long shifts. The textured rubber overmold remains sticky and secure, providing a confident grip even with sweaty or gloved hands.
The Evolution of One-Touch Bit Ejection
Perhaps the most significant day-to-day upgrade is the evolution of the collet system. While the previous iteration featured a "Quick-Eject" button on the front of the motor housing that opened the jaws, users still had to manually pull or shake the bit free.
The new One-Touch system eliminates that extra step. Pressing the front-mounted button now automatically and forcibly ejects the bit. For electricians, carpenters, and mechanics who handle hundreds of bit swaps a day—frequently dealing with hot bits pulled directly from high-torque applications—this automated release prevents burned fingers and speeds up overall workflow.
Comparative Specifications
| Specification | FX1371 (Previous Generation) | FX1372 (New One-Touch Model) |
|---|---|---|
| No-Load Speed | 0–1,900 / 2,700 / 4,000 RPM | 0–1,500 / 2,000 / 4,100 RPM |
| Impact Rate | 0–1,300 / 3,600 / 4,450 IPM | 0–3,000 / 4,000 / 4,550 IPM |
| Max Torque | 2,500 in-lbs | 2,500 in-lbs |
| Bare Weight | 2.8 lbs | 2.4 lbs |
| Kit Weight (5.0Ah) | 4.9 lbs | 4.6 lbs |
| Head Length | 4.75 inches | 4.40 inches |
Implications for the Professional Marketplace
The launch of the FX1372 has distinct implications for both professional contractors and competing tool manufacturers.
For Current Flex Users
If you are already heavily invested in the Flex 24V platform and currently operate using the FX1371, the decision to upgrade requires some thought. The performance gains in speed and torque are negligible because the baseline motor was already exceptionally strong. However, if you regularly work in tight spaces or find yourself constantly frustrated by manual bit removal, the lighter chassis and automated One-Touch ejection system present a compelling quality-of-life upgrade.
For New Buyers and Platform Adopters
For trade professionals shopping around for a brand-new top-tier cordless ecosystem, the FX1372 makes Flex an effortless recommendation. It matches or beats the flagship offerings from Milwaukee, DeWalt, and Makita in pure speed and torque while introducing genuinely useful workflow innovations.
While the tool still carries a bit more physical heft than ultra-compact, lower-voltage offerings when paired with larger high-capacity batteries, the trade-off is more than justified by its relentless, unyielding power delivery. Backed by a competitive 5-year warranty upon registration, Flex continues to prove that it is a serious heavyweight contender in the professional power tool arena.
