Fotga DH-55D Panoramic Panorama Indexing Rotator Ball Head for Camera Tripod Head Two Knobs for locking top platform and panning base rotation, Both top And base rotate independently Includes a removable Arca Mount plate,prove very convenient when a Quick change between equipment is desired on the field The discal clamp is attached by both its center 3/8"-16 threaded hole (via an 1/4"-20 to 3/8"-16 conversion bushing on the top platform and two 1/4"-20 socket hex screws on its sides The panning base has the same diameter as the rotator body and is laser engraved with a degree scale. When this Indexing Rotator is installed onto a tripod, it may also be used as a normal panning base Adopts a very high quality surface finishing and anodizing techniques, Solid and durable