“The lightest, brightest LED cap available. Turns your water bottle into a solar powered lantern. This small, lightweight (just 2.6oz) cap fits on any "standard" water bottle (2" wide mouth) such as Nalgene, Camelbak, GSI and most others, turning your bottle into a solar-powered lantern. With clean, green solar energy powering your lantern there are no more burned out batteries to worry about or replace (adding to our already toxic landfills).”