Amazon offers Prime members the Thermos 40-oz. King Vacuum Insulated Stainless Steel Bottle in Midnight Blue for $20.34 with free shipping. That's the lowest price we could find by around a buck, but most stores charge closer to $30. (However, it was a buck less in October.) It features a twist and pour lid, stainless steel interior and exterior, and the capacity to keep liquids hot or cold for up to 24 hours.