Bought a pack to hang a steel calendar on the side of the fridge when magnetic tape wasn't strong enough.
They arrived in a plastic container, well packaged in a cardboard box and a very serious warning leaflet. Considering how much effort they took to get apart I can see why they say they are not toys.
I put six of the magnets on the calendar and attached it to the side of the fridge. Both the fridge and the calendar are made of thin mild-steel and the fridge has a high gloss coating on top. So far the calendar hasn't moved and seems quite attached. I've not had to glue the magnets to the back of the calendar.