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Performance Tool 5/16 in. X 5/16 in. 12 Point SAE Combination Wrench
Performance Tool 5/16 in. X 5/16 in. 12 Point SAE Combination Wrench

Performance Tool 5/16 in. X 5/16 in. 12 Point SAE Combination Wrench

One tool, two ends: a 12-point box end for tight angles and an open end for quick work, all in one 5/16" SAE size.
Performance Tool MPN W321C In Stock & Ready to Ship
$6.99
Free shipping on orders over $75
Ships within 24 hours · most orders arrive in about 2 business days

About Product Overview

This 5/16" combination wrench from Performance Tool handles the box end and open end jobs on the same tool, so you're not swapping wrenches mid-task. The 12-point box end gives you more angles to catch a fastener in tight spots, while the open end works fast on bolts you can approach straight-on. Alloy steel construction stands up to regular use in the shop, garage, or toolbox, and the SAE sizing covers the 5/16" fasteners common on domestic equipment and hardware.

  • Size: 5/16" (SAE)
  • 12-point box end plus open end
  • Material: Alloy steel
  • Sold individually, carded packaging

The Details Specifications

Brand Performance Tool
Model / MPN W321C
UPC 039564103315
Weight Under 1 lb
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
Price check

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On Amazon, start with these four questions before you click buy.

01

Who's actually selling it

The brand name is on the listing. A different company is in the seller field. Those aren't the same thing, and the second one is who you're buying from.

02

Whether the warranty survives

Most manufacturers only honor a warranty when the unit came through an authorized dealer. We're authorized for Performance Tool. A third-party marketplace seller usually isn't.

03

Where the box came from

Gray-market stock, returns repackaged as new, and outright fakes move through marketplaces constantly. It all looks identical in the photo. It stops looking identical when it fails.

04

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The big boxes don't care if your hardware store survives.

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Authorized dealer · Performance Tool

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