Name: PROTO® 1120 - 5/16" x 3/8" 12-Point Straight Head Satin Double Box End Wrench
Brand: PROTO
SKU: mpn4642393935
Price: 25.29 USD
Availability: InStock
Rating: 5 (1 reviews)

Specifications

Unit of Measure	SAE
Size (SAE)	5/16", 3/8"
End Type	Double
Opening Shape	12-Point
Wrench Shape	Straight
Finish	Satin
Ratchet	No
Reversing	No
Head Type	Straight
Quantity	1 Piece
Weight	0.07 lb
Head Thickness	5/16" (A1), 19/64" (A2)
Head Width	33/64" (End A), 37/64" (End B)
Meets or Exceeds the Following Specifications	ASME B107.100

Features

Satin finish provides corrosion resistance and a slip resistant grip
12 point box end allows for fine indexing, helping to improve speed and access. Fits 4, 6 and 12 point fasteners
Box ends incorporate the TorquePlus™ system.

Product Details

5/16" x 3/8" 12-Point Straight Head Satin Double Box End Wrench (1120) by PROTO®. If you’re looking for a reliable solution to complete your project, this 1st-grade product is right up your alley. Designed utilizing the finest materials, it delivers unmatched levels of durability and strength needed to provide long-lasting service life. Superior in functionality, it will help you make any job easier and faster.

PROTO® - 5/16" x 3/8" 12-Point Straight Head Satin Double Box End Wrench catalog Made In USA PROTO Authorized Dealer

Brand:

PROTO

Part Number:

1120

UPC:

662679060008

Warranty

Except as specified below, Proto Industrial Tools, a business unit of Stanley Black & Decker, Inc. ("Proto") warrants any of its Proto® branded products, including products sold by the Proto Industrial Tools that are marketed as products "by Proto," for the useful life of the product against defects in material or workmanship.

Die Grinders, Torque Wrenches, Torque Multipliers and Torque Testers are warranted for one year, except for calibration which is warranted for ninety (90) days from date of purchase. Torque products can be repaired and recalibrated for a nominal charge at any Proto Authorized repair center or any other such location as may be designated by Proto. Defects in material or workmanship will be repaired or replaced at no cost: all other repairs will be at a nominal charge. Torque products are precise measuring devices that require care in handling. Proto recommends that all torque wrenches be recalibrated once a year or more, depending on usage.

Air Impact tools are warranted for a period of two years from the original purchase date. The obligation to the original purchaser shall be to repairing or replacing, at Proto’s expense a defective tool if returned by the original purchaser within two years from the date of purchase. This warranty does not cover defects or damages to the tool (i) after the warranty period expires; (ii) resulting from misuse or abnormal operation; (iii) resulting from a failure to properly lubricate, maintain or operate the tool; or (iv) resulting from any repair or maintenance services performed by any party other than Proto at all DeWALT Service Centers or a person authorized by Proto to provide repair and maintenance services for this tool.

Disclaimers and Limitation

This lifetime warranty:

Is subject to the disclaimers and limitations described below and is in lieu of all other warranties, express or implied, including the implied warranty of merchantability or fitness for a particular purpose.
Gives you specific legal rights. You may also have other rights that vary by state.
Does not extend to products that have been improperly used, altered, or repaired by any entity other than Proto.
Does not cover the following categories of products: universal sockets, universal joints, thin-wall impact sockets, adapters, and retaining rings.
Does not cover damage due to ordinary wear and tear.
Does not extend to any claim for incidental, consequential, or special damages. Some states do not allow the exclusion of limitation of incidental or consequential damages, so this exclusion may not apply to you.
Proto makes no representations beyond those contained in this Lifetime Warranty.
Employees and agents of Proto have no authority to make representations of any sort beyond those contained in this Lifetime Warranty.

Exclusive Remedy and Claim Procedure

The exclusive remedy under this Lifetime Warranty for products determined to be deficient in materials or workmanship by Proto is repair or replacement with a reconditioned tool of equal value by Proto.
The selected remedy is at the sole discretion of Proto. In no event shall Proto be responsible for more than the original purchase price of the product.

Reviews

(1)

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5 of 5

Remarkable.

My wife's grandfather passed away 40 years ago, I inherited his tools the 1139 Proto 3/4-7/8 wrench is still in use . The wrench is 50+ years old. I have twisted many wrenches of the same size in half, then reached for the Proto and got the job done. I am retiring in 2 years. And the wrench, we'll go home with me, and I will hand it down to my grandson. Thanks

PROTO® 1139 - 3/4" x 7/8" 12-Point Straight Head Double Box End Wrench

Posted by Rick / May 07, 2026

Questions and Answers

(0)

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