This adapter plate has been specifically designed to eliminate unwanted rotation of the spotting scope during viewing. Its universal design means it can be used to mount all makes of spotting scope, no matter what their foot shape (square, rectangular, trapezium), on any Manfrotto two-way head with rapid RC2 connector system. The adapter is made from machine-tooled aluminum with a black anodized finish. In addition to the standard 1/4'' screw, it has two grub set screws to lock the spotting scope securely in position. Manfrotto Universal Anti Twist Spotting Scope Plate 200USS