Made in the USA, Since 1925.
SKU S0107
Available at trusted retailers nationwide
Direct pricing coming soon. See retailer availability below.
The Big 12® Speed® Square stretches the original 7-inch tool to a 12-inch reach, sized for framing big lumber, stair stringers, and full-sheet layouts. Seven tools in one: framing, try square, miter, protractor, saw guide, stair gauge, and out-of-square corner finder. Heavy-gauge die-cast aluminum, 15X stronger than standard aluminum. Includes the Layout Bar with hardware. The Layout Bar bolts to the underside of the square with two wing nuts; two adjustable stop pegs then lock to the exact rise and run you need. Once set, the square becomes a repeatable jig: drop it on the stair stringer or deck framing piece, register the pegs against the edge of the stock, mark, slide to the next position, repeat. Every mark comes out identical without re-measuring. Includes the Swanson® Blue Book for roof and stair layout.
Packaging
Carded w/Layout Bar + Blue Book
S0107
Pick up locally or order online from Amazon, Home Depot, Lowe’s, Walmart, Ace, Menards, or Acme Tools.
Made in the USA
Since 1925
Free shipping
On every order $50+
Pro-trusted
32,000+ verified reviews
In stock at retailers
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Why pros reach for it
01
Try square, miter, saw guide, stair gauge, protractor, out-of-square corner finder, line scriber.
02
Aluminum bar that hooks onto the square head and slides along the body. Use it to extend the square past its 12 in. reach for long stair stringers and full-sheet layouts, to mark parallel lines without a chalk box, and to measure the offset on out-of-square corners that the body alone can’t span.
03
Solid die-cast alloy, 15× stronger than standard die-cast aluminum. Made in the USA.
A closer look
12 in. body, 70% more reach than the standard 7 in. Speed® Square. Sized for framing lumber, stair stringers, and full-sheet layouts.
Solid die-cast alloy, 15× stronger than standard die-cast aluminum.
Patented Layout Bar with hardware plus the Swanson® Blue Book for roof + stair layout.
Built for deck framing, stair stringers, and out-of-square corner layouts.
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