Staedtler Mars® Professional Drafting Kit with 12" Architect's Triangular Scale Mars® Professional Drafting Kit MasterBow fixed leg compass features pushbutton instant leg set and lock, center wheel micro-set adjustment and reversible needle point. Includes sanding paddle, erasing shield, 6" protractor, lead holder, dusting brush, 45° x 45° and 30° x 60° triangles, eraser, two Lumograph® H° and 4H° leads in plastic pouch. With 12" Architect’s Triangular Scale