Neomark&reg;1/4" Male to 1/4" Male Threaded Screw Adapter (10-pack) 10 Precision made 1/4" to 1/4" Stainless Steel (metal) screws,Easy to use. This is a universal adapter spigot stud for the studio use . approx.Total length:20mm approx.diameter:16mm 10 pieces pack.