Controller connection steps(see the last picture) 1. Connect the positive and negative poles of the battery as shown in the picture, the controller will detect the battery voltage automatically ; 2. Connect the solar panel to the controller; 3. Connect the load as show , don't connect it reversely; Note: Please connect in strict accordance with the picture show, otherwise it may cause the controller short circuit; the disassembly sequence is opposite to the connection sequence. Features: 1. Made of high-quality materials, environmentally friendly, durable and delicate. It has a high conversion rate. 2. Dual-output solar panels with USB interface to meet any of your requirements. 3. Environmental protection and pollution-free, realizing the conversion of solar energy to electric energy 4. It has a wide range of applications and can be used in many places, such as automobiles and small household appliances. 5. A solar panel is a device that directly or indirectly converts solar radiation into electrical energy by absorbing sunlight. Compared with ordinary batteries and rechargeable batteries, solar panels are more energy-efficient and more environmentally friendly. Specification: Name: Flexible Solar Panel Material: Polysilicon Solar panel voltage: DC12-18V Solar panel power: 300W(max) USB output: 5V Number of USB ports: 2 Open circuit voltage (VOC): 5V Short circuit current (Isc): 3A Output: USB Size: 43 * 20cm / 17 * 7.9inch Packing Included: 1 X Solar Panel 2 X Alligator Clip 1 X Car Charger 4 X Accessories Note: 1. Please allow 1-3cm (0.4-1.18") difference due to manual measurement and slight color variation for different display setting. 2. Due to the light and screen difference, the item's color may be slightly different from the pictures. Please understand.