Ideal for smoothies on the go, the Oasis "Super Sipper" Insulated Tumbler W/ Silicone Head Straw harnesses double wall vacuum insulation technology to significantly reduce heat transfer by conduction or convection. Drinks remain cold for up to 6 hours without condensation building on the exterior. Made from quality 18/8 grade stainless steel inside and out, this Oasis Super Sipper is highly-resistant to rust, is odourless, BPA-free and built to last a lifetime. Convenient and portable; the Super Sipper features a tight-fitting twist-lid with a silicone seal and a flexible silicone head straw. Perfect for your fast-paced lifestyle all year round, this stylish and reusable Oasis Super Sipper offers an environmentally conscious alternative to plastic bottles.