Swanson Tool Co S0107 “Big 12″ 12-Inch Speed Square Layout Tool with Blue Book – $8.17

First post, be gentle.
12" stair layout speed square, also a great crosscut guide for a circular saw. This set includes Layout Bar for use in determining out-of-square corners when building stairways.
Average price: $21.26
Lowest price since 2016 according to CCC.
https://smile.amazon.com/dp/B0000…UTF8&psc=1