A foot that stops the door. A more long winded explanation would be:
A plastic version of what goes in shoes, cunningly shaped into a wedge such that it may encourage doors to stay put.
Importantly, one side of this is angled and ends up with a lot of ridges when printed. That makes it great for gripping the carpet.
Print one, mirror it and print another. Donâ€™t put in shoe, put under door... (Clearly this is good for 2 doors or just one really stubborn one)