These Mandrels are made to work with our Tube Fly Vise and work with the collets that come with the vise. There are three sizes; 1/16", 1/32", and 1/8" and will handle tubes up to 4" long. We do offer an extra long 1/8" mandrel that will hold up to 8" long tubes. For additional parts and accessories be sure to look at our Tube Fly Vise Accessories page.