SAE flat washers are machined to a tighter specification and have a smaller outside diameter.Flat Washer, Fits Bolt Size #4 ,Brass 50 PK USS flat washers have a large, wider body..
. Socket screws are commonly used in assemblies that do not provide sufficient clearance for a conventional wrench or socket.1/4"-20 Socket Head Cap Screw, Plain Steel, 3/4 in Length, 12 PK A hex key is required to tighten or loosen a socket screw.