Hexalobular (6 Lobe) socket pan head thread forming screws ~type C, metric thread — M 4 x 8 / X20

Bossard · Thread Forming and Tapping Screws for Metal. d1: M4 | L: 8 | d2 max.: 8 | k max.: 3,25 | Hexalobular socket: X20 | t max.: 1,8 | A~: 3,9