This standard specifies hexagon socket head screws with thread specifications M3~M20, performance grades 8.8, 10.9, 12.9, and product grade A. If other technical requirements are required, they should be selected from current standards (such as GB/T 196, GB/T 3106, GB/T 3098.1, and GB/T 3103.1).
GB/T 70.3-2000 history
2023GB/T 70.3-2023 Hexagon socket countersunk head screws with reduced loadability
2008GB/T 70.3-2008 Hexagon socket countersunk head screws
2000GB/T 70.3-2000 Hexagon socket countersunk head screws