3D Square - Holiday Gift Guide for Tool Lovers - Bob Vila
Carpenter's squares let you draw a line only across one surface of a material. This simple but ingenious twist on the standard square incorporates a 90-degree “fin” that sits flat against the side of what you’re working on so you can mark both its length and depth. Plus, attach the pencil holder and use the fin as a guide, and you can draw a straight line down any length of wood. It’s definitely cool to be this square. Available on Amazon; $52.86.