Radius Checker, black anodized aluminum construction. 12 radius checker points: flat, .75", 1.25", 1.5", 2", 3",  4",  6", 12",  24",  36". Ideal for checking or confirming outside radius points on panels or to aid in layout of templates, bucks, forms. Also checking E wheel, planishing hammer and calibration dies shapes. 12 1/2" long X 3 1/2" wide