Fotasy 1/4" Male to 1/4" Male Threaded Screw Adapters (5 Pieces) 5 Precision made 1/4" to 1/4" Stainless Steel (metal) screw This is a universal adapter spigot stud for the studio use . Total length: App 20mm The length is 20mm, and the width is 16mm Made of metal, solid and durable, Silver Plated Surface