Our favorite mug, now in the GSI Eco line, leads the way when it comes to materials and manufacturing. Made from BPA-free, non-leaching polypropylene and wrapped in a recycled plastic (rPET) cloth. The insulated sleeve, non-slip footing, and sealable sip through lid keep the contents warm (or cold) and free from spills, trail dust, and critters. A sturdy webbing handle gives a great grip and collapses flush for compact storage in your pack. The Infinity Mug with graduations for easy measurement holds 17.5 fluid ounces but weighs just 3.5 ounces, making it light enough for even the choosiest, ounce-shaving through-hiker.