They are used to install lots of threaded studs to protrude the exact same length from the surface of the part. The knurling allows finger installation until a wrench is needed.
304 Stainless
I made then so the stud length is governed by the body length of the tool. These are for 3/8, 5/16, and 1/4" studs. The 1/4" has three bodies so far for specific lengths. We install LOTS of studs and it was too time consuming using a collet type stud tool to try to get studs of the same length installed to the EXACT same height....until now! We have a +-.010" installed height tolerance, and can now set them within a few thousandths. Just insert the stud into the tool and screw it into the part until the lower face of the tool contacts the part, and remove the tool.
