Our Middle Child Cup can hold nearly half a litre of water making it the perfect multipurpose side-kick. The lid is reverse force, a fancy way of saying; It's a very clever lid that actually stays on. YES, you heard right, it stays on! What else you need to know: Holds up to 16 ounces or 473.176 MLS Borosilicate Glass is lighter & stronger than ordinary glass; It’s fancy, but still needs to be treated with care Hot drink lid only is included Middle Child base & lids are interchangeable with our Smoothie Cup Fully enclosed, non-slip silicone base We're Australian and we designed it here