The Avanti Fluid Stopper lid helps you to stay hydrated while doing other tasks at the same time. It's so simple to use, all you need to do is simply press the leak proof opening button inwards to release and again to close between uses. Fluid stopper lid suitable for Avanti Fluid bottles of 350ml and 500ml capacity Leak proof Easy to use when multitasking Perfect for outdoor activities, school, work, or when you're on the go Designed in Australia Dishwasher safe