HEX BOLT DIN 933 / ISO 4017 are fully threaded, have external coarse machine screw threads and, like other hex head screws, are used with both tapped holes and nuts. Their dimensions are similar to ISO 4017 and are available in Class 8.8, 10.9 and 12.9, all lengths are fully threaded. Length is measured from under the head to the tip. DIN 933 Hex Head Cap Screws are similar to ISO 4017, Hex bolts are currently being used in major construction and repair projects around the world. Being the industry-leading Hex bolt manufacturer China and Hex bolt exporter from the country, our products are much sought after. Our hex bolts are being used for many different applications across construction, repair, automotive industries. They can be used for fastening wood and steel. They are used in major construction projects such as buildings, bridges, marine docks.