Hex socket cap screw according to ANSI B18.3 standard with UNC (Unified National Coarse) thread, strength class 12.9, plain (uncoated) surface. The design corresponds to ISO 4762 but uses inch threads. The plain finish is suitable for dry or controlled environments or when the screw will later be coated, for example with painting, flake coating, or hot-dip galvanizing (HDG). Class 12.9 provides very high tensile and clamping strength for machinery, equipment, and imported constructions where inch threads are standard. Available in multiple lengths and dimensions from SWEBOLT & BOTNIA BOLT.