Flip flops tumblers. Flip Flops Insulated Tumbler Drinkware "Sunshine Sandals" - 24 oz - Set of 4. Great to use indoors or out, these 24 oz durable plastic insulated tumblers have a pattern of colorful flip flops. These insulated tumblers keep your drinks cold longer and this size holds a lot! These come in a boxed set of 4. We recommend hand washing.