Make your own threads instead of searching for left-hand fasteners, which can be expensive and hard to find. A cut above lower-quality dies that can leave inferior threads, these are machined in the U.S. to precise dimensions for accuracy and consistency. They are adjustable, so you can create a shallow thread that makes it easier to get the die started on the first pass. Turn the set screw to open the die to its largest diameter. Then rotate the die with a round die wrench and adjust the screw as you make additional passes to reach the proper thread size.