SWEBOLT & BOTNIA BOLT supply fully threaded hex bolts ISO 4017 / DIN 933, in property class 8.8 per ISO 898-1, with a plain (uncoated) surface. These bolts are primarily used in dry or indoor environments, but can also be surface treated on request through our partner network. The plain finish offers a cost-effective solution for construction, industrial, and maintenance applications where corrosion protection is not required as standard.