Products for bench top machinists | LittleMachineShop.com

Screw Checker, Inch, PEC

Screw Checker, Inch, PEC - Main image
$19.13 $26.95 In stock

Screw checkers made by Product Engineering Corporation (PEC) made in the US are the industrial standard for precision and durability.

Made from a high-quality chrome-plated carbon steel which offers superior wear resistance and long-lasting, crisp graduations. Fully hardened, tempered and etched with precision.

Tired of guessing thread sizes or making multiple trips to the hardware store? The PEC Fractional Screw Checker is the essential bench top tool for every machinist.

This precision-machined gauge allows you to instantly and accurately identify the size, pitch, and length of any standard American fractional screw.

Whether you are sorting a "junk drawer" of fasteners or verifying hardware for a critical assembly, our screw checkers provide a foolproof way to ensure you have the right fit every time.

  • Comprehensive Range: Accurately identify common fractional sizes from #4 through 1/2" in both National Coarse (UNC) and National Fine (UNF) threads.
  • Precision-Tapped Holes: Every hole is tapped to industrial standards, ensuring that if it threads in, it's the right size—no more stripped threads or forced fits.
  • Integrated Length Gauge: Features a built-in ruler to quickly verify the overall length of flat-head or round-head screws.
  • Shop-Ready Design: Compact enough for a toolbox, yet pre-drilled for easy mounting to a workbench or wall.
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Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

George ★★★★★

The chrome plating on this one feels rock-solid, not flimsy like the cheap plastic gauges I've used before. It's clearly built to take a beating in a shop.

Nicholas ★★★★★

Finally got around to replacing my old worn-out set and the chrome-plated finish on these is noticeably smoother. They sit perfectly in the screw slot without any wobble, which makes quick work of adjusting saws and jigs.

Olivia K. ★★★★★

I've used these for years in the shop, and the chrome-plated carbon steel holds up way better than the plastic ones I had before. The inch sizing is dead-on for every standard bolt I've checked, so no more guessing on thread sizes.