Aristo adjustable set square 12" with inking edge. Made of crystal-clear PLEXIGLAS 3.5mm thick, continuous facet. One side of the isosceles triangle is adjustable so that the functionality of a square and a protractor can be combined. The degree scale 0' to 45' and 90' to 45' in 1' and 1/2' increments is offset. In white, continuously adjustable and fixable with a chromeplated screw. A red mark enables exact adjustment. AH23412.