dokio 300w 18v portable solar panel kit (41x21inch) folding solar charger with 2 usb outputs for phones work for 12v batteries/power station agm lifepo4 bluetti eb240 rv camping trailer car marine dokio <p><b><br></b></p> <p></p> <p></p> <p><b>if there is any problem with the product, please feel free to contact us, we will provide you with a satisfactory solution within 1-2 days and will not let you suffer any loss.,this product is primarily designed to charge batteries. using without batteries is primarily providing power to the usb ports. if you want higher power generation efficiency, you can buy mppt and use it</b></p> <p><b><br></b></p> <p><b>if your solar generator has a controller built into it, you may be able to just connect this solar panel (without its included controller) directly to your solar generator, without the voltage regulation provided by the controller your chance of cooking the battery by overcharging is possible. </b></p> <p><b><br></b></p> <p></p> <p><b>not day-in day-out exposure. sun damage to fabric case is most likely</b></p> <p><b><br></b></p> <p></p> <p></p> <p></p> <p></p> <p></p> <p><b><i>question:</i></b> are this units <b>waterproof?</b></p> <p><b><i>answer:</i></b> <b>yes,it is waterproof ,but meant for temporary or emergency use only. not designed for permanent installation or prolong weather exposure.don't leave them out at night or in bad weather.</b></p> <p><b><br></b></p> <p><b>question:</b>does this kit come with some sort of stand?</p> <p><b>answer:</b>there is no stand. i lean in against my rv or rv tires. i have been very happy with this panel set though</p> <p><br></p> <p></p> <p><b>question:</b>on solar panels before i purchase i want to know, if you put on the roof of the house, how long will last before go bad?</p> <p><b>answer:</b>you don’t want flexible panels for that purpose. get the hard panels. they last longer. </p> <p><br></p> <p></p> <p></p> <p><b><i>if any accessories are missing or damaged, please contact us for replacement in time</i></b></p>