UltimateAddons 3 prong socket plate is designed to allow UltimateAddons 3 Prong holders and cases to be connected. The socket slots securely over the 1 inch (25mm) ball connector and is tightened with a nut for the optimum viewing position. This is now supplied with new locking mechanism on the 3 prong attachment. This is ideal if you already own an UltimateAddons 3 prong holder or case, if not there are plenty holders to choose from