I didn't like any of the available lever style door locks to keep kids out of doors they shouldn't get into. They involved screwing into or door wrecking mounting tape.

So I designed this, simple enough it prevents the lever from being pulled down (which is what makes it easy for kids to access) but an adult can still easily use the door by lifting up. It worked very well for us.

It's made to fit Weiser Halifax door levers, but it may fit other square shaped models as well.