I bought the item to help keep the battery on our camper maintained during a long camping week. We typically could only make it 2 1/2 days on a battery before we needed to recharge with the solar maintainer we made it a little over 3 days. It helped but doesn’t bring the battery to full charge after a days use. A 5 watt would probalby work better for us.[keyword]solar battery charger[/keyword][babs_template]solar+battery+charger, 2, , 41979, All, 0, 1344, [/babs_template]