I "discovered" PEC tools of California and was so impressed I bought some of their stuff to put it to the test of daily use. I am still impressed and I now recommend PEC's premium line of solid squares. PEC's Solid squares are just that - solid metal, no moving parts, and VERY accurate. I have and use several different sizes of solid squares in order to match the square to the job at hand; the price of these squares permits this luxury! 2 inch long blade. Made from high quality harden tool steel. Has true right angles; both inside and out. Beams and blades are precision ground and hardened. Length of blade is measured from inner edge of beam to the end of the blade. <iframe width="560" height="349" src="" frameborder="0" allowfullscreen="" data-mce-src="http://www.youtube.com/embed/n_dZNLr2cME?rel=0&hd=1">