Hello There, I have these magnets ordered by an "invisible" to have closure for my rat cage. The cage is made of metal, we have installed new doors and there is the frame made of aluminum, etc., we wanted no latch outside turn have so we have the mini magnets glued to the aluminum, and now hold to make the magnets that really deliver what they promise, rats for which no outbreak of chance and from the outside it looks great! The magnets are really great =)