A large durable Nylon thumbscrew engages the Stainless Steel Clamping Pusher. The AP-7 works with a large array of 1/4-20 mounting applications, using the ¼-20 female thread hole or the included Accessory Mounting Thumbscrew to attach the cold shoe to a variety of flash brackets, light stands or audio visual mounts. Anti-Rotation Set Screw with hex key, is useful for more permanent installations to keep the shoe from loosening or becoming misaligned. The AP-7 mounts natively to the M3 portion of our flash brackets. Great to eliminate cords with radio transmitted flash units. Made in USA, Assembled in Charlottesville, Virginia..