Automatically adapt to the cell voltage 12V/24V, making it possible to easy operation. This product control the ba-ttery voltage and turn on the circuit. Also, when the ba-ttery voltage rises to a certain level, it will stop the ba-ttery charg-ing. Specifications: Model: YCX-916-10A Material: ABS+ROHS Item color: Blue & Black Rated Current: 10A, 20A, 30A, 40A, 50A, 60A (optional) Rated Voltage: 12V/24V Max PV Voltage: 50V Max PV Input Energy: 390W (12V) 780W (24V) Item Weight: 134g / 4.73 ounce Package Weight: 165g / 5.82 ounce Item Size: 125 * 84mm / 4.92 * 3.31 in Package Size: 135 * 80 * 40mm / 5.31 * 3.15 * 1.57 in Notes: 1. Make sure your ba-ttery has enough voltage for the controllers to recognize the ba-ttery type before installation. 2. The ba-ttery cable should be as short as possible to minimize loss. 3. The regulator is ONLY suitable for le-ad acid batteries: OPEN, AGM, GEL. (NOT suitable for nickel metal hydride, lithium ions or other batteries) 4. This controller can ONLY use photovoltaic panel as char-ging source, do NOT use D C or other po-wer su-pply as charg-ing source. Packing List: 1 * Solar Charge Controller