... . 2. material: steel, 3. finish: zinc non-standard flat head socket rivets with internal thread1.Standards:DIN ,ANSI/ASME,BS,GB ... -standard screws, egg neck bolt, fishbolt, countersunk head bolt. Expansion bolt, expansion screw.etc.Specialized in manufacturing fasteners such as bolts ... ANSI Grade 2, 5 and 8.7. Various nuts, flat gaskets, spring washers, mechanical bolts, tapping screws, fibreboard ...