STAEDTLER Mars Geometry Set Square with Grip, White. This set square is a useful and versatile piece of equipment, offering a protractor, ruler, and 45° square in one. The ruler along the hypotenuse is graduated in mm and runs from 0 to 7cm from the centre in both directions. The protractor scale runs from 0 to 180 and also in reverse. The angle markings are carried forward to the edges. Two vertical scales are incorporated, running from 0 at the base to 3.5cm. Made from transparent polystyrene with ink studs, bevelled edges, and a removable grip. The triangle base measures 16cm. Part number: 568 36.