The Latest Innovation in Science Gifts has Arrived. Introducing The Calculated Chemist's Flask Tumbler, a premium 500 mL stainless steel drink bottle engineered with precision and inspired by the iconic Erlenmeyer flask. Crafted from durable 304 stainless steel inside and out, it features double-wall vacuum insulation to keep drinks hot or cold for everyday carry. Product Features: * Double-wall vacuum insulation to keep your drink hot or cold for longer. * Durable 304 stainless steel for long-lasting use. * Spill-proof twist-on lid for worry-free portability. * 500 mL volume capacity * Eco-friendly: reusable, BPA-free, and VOC-free powder-coated