17 oz stainless steel body with 4 oz indicator lines on the interior of the cup. The BPA-free plastic lid is twist-on with a flip-open top lined with silicone at the mouthpiece closure for a no-mess spill-free design. Keeps drinks hot or cold for 6-12 hours. Bring along with your pup on the next adventure on the water, in the sunshine, or at the lake house.