Starrett C434-12-4R Combination Set with Square, Center and Reversing Protractor and Satin Chrome blade Often called try squares, bevel protractor, center gauges 12 inch satin chrome blade, 4R graduation: 8ths, 16ths, quick reading 32nds and 64ths Reversible lock bolts Square and protractor head Double reading double 180 degree protractor scales