RND Spare Battery Charger for Samsung Galaxy S and S II Smartphones (with USB output) RND power solutions Spare Battery Charger with USB Output charges a spare battery. Simply connect your USB charging cable or car charger to start charging. Compatible with: Captivate Epic 4G Epic 4G Touch Fascinate Galaxy S 4G and Vibrant models RND Power Solutions products comes in professional retail packaging and offers a 1 year hassle free warranty. 100% Customer Satisfaction is our Goal. PLEASE BE CAREFUL when buying products on Amazon and only buy from trusted sellers. Sellers without authorization may sell an inferior quality product carrying no branding. Examples of some trusted sellers would be RND Power Solutions and Amazon. Authentic RND Power Solutions products will have our branding on the product and packaging.