The vertical blade of this specially-designed square features 60-degree beveled edges which provide excellent visual line contact for more accurate scribing and marking. Expertly crafted of high-quality tool steel, the hardened beam and blade are ground and lapped to ensure parallel and straightness with square accuracy of .0001". Beam is 5/8" x 3/4"; blade length is 4" from the inside edge of the beam, total length is 4-3/4".