Kupo 1" Conversion Adapter 1/4"-20F to 1/4"-20M (Set of 5). Convert any 1/4"-20 receiver to a male 1/4"-20 stud. It is 25.4mm long. Tightens securely into place using an allen key or hex key. Mount spigots tripod heads or anything with 1/4"-20 receiver in difficult places.