The 522A is a dual circuit, progressive zoom remote control unit for the Panasonic AG-DVC-30, AG-DVC-60, AG-DVC80 and AG-DVX100A. Built into a video head pan bar suitable for Manfrotto models 700RC2 and 701RC2. The dual circuit allows you to choose between a zero power consumption "analog" mode for basic functions (record/stop and progressive min-max zoom via a professional zoom wheel) and a 3 AA (1.5 volt) battery-powered, advanced, customisable "digital" mode. The digital mode gives you the record/stop function, and the zoom wheel can be used to control one of three preset maximum zoom speeds or a customisable maximum speed which you can set to exactly the level you want. The "custom" zoom speed setting remains in the unit’s memory even when batteries run down, until you decide to change it. In addition, for all options except the slowest preset speed, you can choose between progressive zoom speed (the further you rotate the zoom wheel, the faster the zoom) and fixed zoom speed (irrespective of the rotation applied to the wheel, zoom speed remains constant) by pressing the button once (progressive) or twice (fixed). An LED shows you which speed you have selected. The 522A also allows you to set left- or right handed operation by changing zoom wheel direction. 522A does not come with any parts to fit to the head, but instead utilizes the pan bar clamp that comes with 700RC2 and 701RC2 heads.