Nuts Hex nuts, Hex heavy nuts Lock nuts (pal nuts), Shear nuts, Hex Flange nuts, Hex Thin nuts, Hex nuts 3D (coupling nuts) Wind nuts, square nuts, Round nuts, Rectangular nuts, Channel nuts, Slotted nuts, Castle nuts, Prevailing torque type hex nuts (also with nylon insert) and Hex dome cap nuts. 2.5 mm Nuts 3.5mm Brass 3.5 mm Gold 3.5mm Zinc 4mm Square 5mm 5mm Hex 5mm Rectangular