* Easy to use: The upper end is a dual interface of Swiss Arca and Picatinny rails. The knob adjustment can accurately adjust the distance and effectively make the adapted product and interface perfectly. The lever-lock design can achieve one-second locking and release. * Easy to install: The lower part is a one-piece aluminum body design, the dovetail plate allows it to be directly mounted on the ball head and the 3/8" UNC screw hole allows it to be directly mounted on the tripod tray. 1/4" and 3/8" UNC external interfaces increase the range of use of this product.