Aristo Adjustable Set Square 12"

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.