Alvin 30/60/90 plastic drafting triangle. Quality 4" drawing triangle is constructed of molded polystyrene plastic 0.10" thick, with double-beveled inking edges and double-beveled center cut-out finger lifts. Popular drafting triangles fluorescent light has an illuminating effect on the drawing by accentuating the triangle edge. Supplied in poly bag with hanging hole. Alvin 30/60 degree fluorescent orange inking drafting triangles are made in the USA.