DIN 7991 CSK Allen Key Bolt
A Flat head screw includes a flat head and a shank with threads. The flat head is integral with a coupling end of the shank and includes a top face and a bottom face. A socket is defined in the top face and extends through the bottom face into the coupling end. The coupling end includes an enlarged coupling section having a top end contiguous to the bottom face. The enlarged coupling section further includes a lower end with a tapered section. The threads extend to the enlarged coupling section. A minor diameter of the threads on the enlarged coupling section is greater than that of the threads on the remaining portion of the shank by about 5-25%. A length of the enlarged coupling section is greater than at least one pitch of the threads for forming at least one thread on the enlarged coupling section.
Grade : 8.8, 10.9, 12.9, 304, 316, B7, L7
Carbon Steel, Mild Steel, Alloy Steel & Stainless Steel
Metric Size: M3 TO M24
Imperial Size: 1/4” TO 1”