The 400ml Freezbot Bottle is manufactured of high-quality Plastic. The body is curved and transparent and features a screw cap with a convenient carry mechanism as well as a freeze tube, the freeze tube can be removed, placed in the fridge or freezer to ensure it is cold, removed from the fridge or freezer, and inserted back into the bottle. This helps to keep liquids colder, for longer, especially during hotter days. *Please note that this product is not microwave or dishwasher safe*