Specifications: Rated Voltage: 12V 24V Auto Application: Solar System Controller Current: 10A/20A/30A With Timer and light sensor,it could work for solar light system. Only For off-Grid PV Solar System. For 10A 12V Pv System: 120W Solar Panel,12V Lead-acid Battery,21V for Max input Voltage For 10A 24V Pv System: 240W Solar Panel,24V Lead-acid Battery,42V for Max input Voltage Safety Instructions: 1.Make sure your battery has enough voltage for the controller to recognize the battery type before first installation. 2.The battery cable should be as short as possible to minimize loss. 3.The regulator is only suitable for lead acid batteries: OPEN,AGM, GEL it is not suited for nickel metal hydride, lithium ions or other batteries. 4.The charge regulator is only suitable for regulating solar modules. Never connect another charging source to the charge regulator. Features: 1.Build-in industrial micro controller. 2.One-key setting,digital display,auto memory function. 3.Fully 4-stage PWM charge management. 4.Build-in short-circuit protections,open-circuit protections,reverse protections,over-load protections 5.Dual mosfet Reverse current protections ,low heat productions. System Connection: 1.Connect the battery to the charge regulator - plus and minus.it will show 1 ,if it detects 12V battery, 2 if it detects 24V battery. 2.Connect the photovoltaic module to the regulator - plus and minus. 3. Connect the consumer to the charge regulator - plus and minus. The reverse order applies when deinstalling! An improper sequence order can damage the controller! Size: 133x70x32mm/5.2x2.7x1.3" Quantity: 1 Pc Note: Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Contents: 1x Solar panels Battery Charge Controller 1 x User Manual