Walmart offers the Ozark Trail 30-oz. Stainless Steel Tumbler in Stainless Steel for $8.74. (Several other colors are available for a buck more.) Opt for in-store pickup to avoid the $5.99 shipping fee. That's a buck below our mention from a month ago and the lowest price we've seen. (It's the best deal now by $5.) This BPA-free tumbler is double-walled and vacuum-sealed.