M6 x 20 Button Head Allen Screw
High Tensile Self Colour Black Screws are used when Strength is paramount,
High Tensile Button Head Allen Key Self Colour Black Screws
Metric Threaded Screws, Various lengths from 5 to 60mm, M3, M4, M5, M6,
Button Head Screws
This is a type of cap screw with a hexagonal recessed drive.
Other head designs include button head and countersunk head, the latter designed to be seated into countersunk holes.
A hex key (sometimes referred to as an Allen wrench or Allen key) or hex driver is required to tighten or loosen a socket screw.
Socket screws are commonly used in assemblies that do not provide sufficient clearance for a conventional wrench or socket.