Take any ruler add a stop and repetitively accurate marks are at your finger tips. Sized to fit rulers up to 2-1/4-inches wide exactly like our Woodworking Rules and has a length of two inches. It can be positioned anywhere along the rulers length. The screw, posts and knob are machined from stainless steel. The body parts are machined aluminum blocks and anodized for decades of accurate performance. Like all Woodpeckers woodworking tools, these precision stops are machined in house to ensure top notch quality and full control of every step of the manufacturing process.