To develop one of the world's premium rafter squares, Johnson first had to engineer the EZ-Read™ finish, its revolutionary anti-glare protective coating that diffracts sunlight rather than reflecting it, so it looks as crisp in full sun as it does in the shade. The EZ-Read™ finish also increases friction to better secure your square against your lumber when using it as a saw guide. The Johnny Square® is highly durable and accurate. Its solid aluminum body construction with CNC-machined edges ensure an accurate reading every time. This rafter square also features continuous scribing notches that are ideal for ripping at 3-1/2 in and 5-1/2 in as well as handy markers that measure 2x4 board dimensions of 1-1/2 in, 3 in and 3-1/2 in.