Socket screws Socket screws,also known as Allen head,are fastened with a hex allen wrench. Relative: DIN 6912 - Low Head Socket Cap Screws With Pilot DIN 7984 - Socket Low Head Cap Screws DIN 7991 - Flat Socket Head Cap Screws IFI Fastener-7-Machine Screws-Round Head Bolts-Socket Screws-Structural Bolting-Tapping Screws