You are looking at one brand new Tandy Leathercraft Engraved Domed Screw Post. This item 7400-03 has a post that measures 5/16" long (7.9 mm) and a cap diameter of 3/8" (9.5 mm). The post is threaded which allows you to open and reafix as needed. There are various other leathercraft kits, stamps, dyes and tools avaiable in our stecksstore. If you are interested in additional quantities, please feel free to contact us. Please feel free to message with any questions. Thank you for looking