A simple, elegant and robust lift flap
Barely visible fixings and maximised graphic area, on a lift flap that can even be cut to shape
Reveal the answer to a challenge, or punchline to a joke
Show two versions of a single view - then and now, above or below a water line, outside and inside a building, a vehicle, an engine
Explain a mysterious image with hidden,
lift-to-discover labelsCover a light-sensitive item
Hide a treasure box or cache
