400ml Diamond Tumbler has a unique design with a diamond texture effect. Its special copper plating coating keeps your liquids either warm or cold, so you can use it during all seasons. The tumblers in Diamond series have a special screw lid, which is good for heat conservation. In addition, these tumblers also have a removable filter, that can be used for making tea or if you have put ice cubes or berries inside your drink, this filter prevents them from pouring out while drinking. Thanks to the stainless steel, used in both inside and outside of the bottle, it has an outstanding durability; even after a long-term use. The tumbler also has an anti-skid bottom silicone and thanks to the wide round outlet it is easy-to-clean.