Sale price expired July 11, 2014
Take 60% off the High Sierra Wave 50 at Rakuten.com, dropping the price down to $19.99 (for the black style, the other 2 colors are $5 more).
From the site: "1.5-liter hydration system has easy-access fill opening that accepts most brands of water filters. System is BPA free and antimicrobial."
