Alvin professional fluorescent orange inking drafting triangles are constructed of molded polystyrene plastic 0.10" thick, with double-beveled inking edges and double-beveled center cut-out finger lifts. Fluorescent orange color reflects light on the drawing by accentuating the triangle's edge. Supplied in poly bag with hanging hole. 45 degree and 30-60-90 degree available in several convenient sizes. Alvin FT fluorescent orange inking drafting triangles are made in the USA.