Phot-R 1/4" to 3/8" Spigot Stud Adapter with Male Threaded Screw for Photo Studio Light Stands This adapter has a 1/4 screw on one end and 3/8 screw on the other, allowing you to attach it to a variety of photography accessories Used to join 2 pieces of photography equipment that have different sized female mounts Can be used with a variety of equipment and accessories such as flash units, studio lights, tripods, flash brackets, etc. Easy to add and remove