This disc is a soap tool for 3" PVC Pipe molds.  Its designed to fit #6/32 or #8/32 Metric to 1/4" All thread rod.  Can be found at your local hardward store.    You are buying the disc only.  Im currently out of mold kits and All thread Rod.  

Pull Through Soap Tool Jar Lid 3" PVC molds Can be cut to 2.75"

Size in Inches