1) size: 3/16'', 1/4'', 5/16'', 3/8'', 1/2'', 5/8'', 3/4'', 7/8'', 1'', 1-1/8'. 2) material: steel, alloy aluminum, stainless steel. 3) head type: round head, flush head, truss head. 4) application: used for a wide range of applications such as vehicle, railway, wagon, bridge, construction, aviation, container, mining, large-scale steel structure, electrical establishment etc. Lock fasteners provide high mechanical intensity and uniform clamp force, it is quite easy to install with firm riveting, consistency and control. It is a type if excellent fasteners called never loosing fastener due to good vibration resistance and guard against theft. Ordinary plastic bags and carton packaging.