This listing is for a set of 20 screw in conversion hub studs. Simple to use, these screw into the bolt holes in the wheel hub just as your original bolts would. These studs are used to convert vehicles which use bolts to a nuts and stud fitment. This can make fitting wheels easier and quicker (often used on competition cars to speed up tyre changes). These are also helpful when using spacers as the spacers will stay in position when you fit the wheels. Over all length of studs is 80mm 15mm of thread to screw into hub with a 15mm blank section. 50mm thread to fit the wheels Made from strong 10.9 grade steel.