These Amazon Prime Day deals on CamelBak hydration packs have them for their lowest prices of the year. They have men’s, women’s, and even kids’ packs on sale. Kids Hydration Backpack (50oz) $37.29 (38% off)A kid-friendly version of CamelBak’s iconic packs. has long been a go-to hydration pack for serious cyclists and hikers, and this updated version holds a full 100oz reservoir—plenty for long days on the trail. It’s a reliable men’s hydration pack that doesn’t skimp on storage or comfort.