Rapidesign Bolts and Nuts Template (#R57) ranges from 1/4" to 1" as measured across the flats. Contains 13 hexagons in 1/16" increments. 13 circles serve as tangent or chamfer circles for hexagons and bolt body diameters. Includes 9 cut-outs for square heads and nuts. Made in USA. Rapidesign has the world's largest selection of drafting templates for architects, builders, engineers and graphic designers.