Socket screw, hex, countersunk, stainless steel, GR A4-316, STD, 12 x 1.75 x 40 mm, Fastbolt.

A countersunk screw is a type of fastening that sits flush with the surface of the material it occupies. These screws typically are used so that you can cover them easily with either a screw cap or piece of wood. Stainless steel is a family of iron-based alloys that contain a minimum of approximately 11% chromium, a composition that prevents the iron from rusting, as well as providing heat-resistant properties.