You buy a bottle of some delicious (perhaps expensive) drink but don’t want to consume it all at one sitting: what can you do?
Today’s invention is a bottle design which allows a certain amount to be drunk and the rest saved, whilst limiting access to the remaining contents by air.
The hour-glass-shaped bottle would be of plastic and contain several constrictions. When one has removed content to the level of any one such neck, the upper part is twisted so as to close the narrow gap above it and then pressed downwards so as to partially crush the upper portion of the bottle.
Reattach the lid tightly to prevent air entry and the bottle stays in crushed mode, protecting the contents. Untwisting and extending the squashed neck again allows pouring the next glassful.