M5 - 5mm Socket Cap Screws A2 Stainless DIN912. They are tightened using a hexagon wrench. They are fastened with the use of screwdriver with hexagonal insert bits or simply using an Allen key. They are made of A2 (304) stainless steel, A2 stainless is the most common type of steel used for the manufacture of fasteners and is suitable for general use.
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