Countersunk hex socket screw according to ANSI B18.3 standard, UF6S type with UNC inch thread, in stainless acid-resistant steel A4. The countersunk head allows the screw to sit flush with the surface after installation. UNC thread is used in assemblies with imperial dimensions, commonly found in imported machinery and equipment. A4 stainless steel provides excellent corrosion resistance and is suitable for outdoor, humid, and chemically exposed environments. Used where flush mounting and high corrosion resistance are required. Available in multiple sizes from SWEBOLT & BOTNIA BOLT.