M4 x 20mm Socket Countersunk Screws (DIN 7991) - 7075 Aluminium Anodised Black Socket Countersunk Screws feature an internal socket drive and are fastened with a Hexagonal\/Allen key. The slanted neck and flat top allow for Socket Countersunk Screws to lay flush with the fastened surface or raised when paired with a Cup\/Countersunk Washer. These Socket Countersunk Screws are made from 7075-T6 Aluminium. Known for its high strength-to-weight ratio 7075 Aluminium is one of the strongest commercially available grades of aluminium and is also extremely lightweight. These Socket Countersunk Screws have been precision manufactured in house from 7075-T6 Aluminium using state of the art CNC Machines to DIN 7991. Due to this, unless the item is deemed faulty, this item is non-returnable and non-refundable. For larger quantities or items not listed, please email and one of our team will provide you with a quotation. M4 x 20mm Socket Countersunk Screws (DIN 7991) - Aluminium 7075 Anodised Black