Many of our favorite apps and websites started out as simple concept sketches on paper. And let’s be honest — the best designers tend to be perfectionists. The Pixel Ruler ensures that those early sketches are perfectly aligned and scaled long before they ever make the transition to digital.

This ruler is composed of stainless steel, providing markings scaled to 150 PPI (pixels-per-inch) as well as handy marks for mobile, tablet, and widescreen (laptop) layouts. The backside features a non-slip grippy surface for ease of use, and each ruler comes with a Zebra mechanical pencil.

Pick it up for $26.95.