How it works
A press-and-turn lid is two parts nested together. The outer cap is what your hand touches. The inner one is threaded onto the tin. Left alone, the outer cap rotates freely around the inner one, so the turning force has nowhere to go.
Press down and the two engage. Now turning the outer cap turns the inner one, and the tin unscrews. Let go and they disengage again on their own, which is why it resets every time without anyone thinking about it.
Why that stops a child
Because it needs two things at once. A small child will happily turn a lid for a long time and get nowhere, because turning is not the part that matters.
It also fails safe. There is no spring to wear out and no separate part to lose. The mechanism is the geometry of the two caps.
What it suits
Anything opened often. The closure survives repeated use better than most, and it is fast once you know it, so it works for a product somebody goes back to daily.
Round Tin and Tin Tube both use it. On a tube it is the same idea in a narrower diameter, which is why single pre-rolls and cartridges end up there.
The one thing people get wrong
Customers who have never met one try to twist harder. They do not press. It is worth a line on the pack or the insert saying press down and turn, and it costs nothing to print.
Once somebody has done it once, they never need telling again.
Hold one before
you specify it.
Tell us what you're packing and we'll send the formats that suit it.