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The Mainstays 40 oz Stainless Steel Tumbler is a large handled cup with a lid, a reusable straw and double-wall vacuum insulation. The 40 oz capacity and big side handle make it a direct rival to Stanley's 40 oz Quencher and the Owala 40 oz tumbler, but it keeps things simple: one black finish, a straw lid and no extra lids or straw types in the box. Owners rate it well for everyday hydration and say it keeps drinks cold for hours, though some find it heavy when full and report the lid or straw can be fussy. It suits desk workers, commuters and anyone who wants a big cup without paying premium-brand money.
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Lowest price we've seen: $12.96 on Nov 12 at Walmart. Tracked across 1 store since Nov 12.
With 4.4 out of 5 from over 1,000 ratings, owners mostly praise the size, the handle and how long cold drinks stay cold. Complaints center on weight when full, lid fit and cleaning the straw.
The Mainstays 40 oz Stainless Steel Tumbler holds water, coffee, and other everyday drinks. It has a double-wall vacuum-insulated stainless steel build and a simple black finish.
It comes with a lid, a reusable straw, and a large handle for sipping and carrying.
