Very often today people will find Rare Earth Magnets that are used in retail packaging production. This is most often the construction of paper boxes that have one or more flaps that can be moved.
Often seen in the collection of high-class children's books, DVD collections, or things like Craft type kits that are found packaged in cardboard. This is considered to be a replacement for hook and loop type fasteners (eg Velcro) found in old-style boxes.
You can buy various types of rare earth magnets at Rochester Magnet
There are two configurations that must be considered.
1) Using two rare earth magnets
2) Using one rare-earth magnet, and one piece of ferrous metal
Choosing which option to choose depends on several factors:
Gap – what is the total distance between magnet/metal pairs?
Feel – how much power you want the end-user to apply when opening
Because the rare earth's magnetic properties are rather fragile, it is usually recommended that during the assembly of the box that the two parts (two magnets, magnets/metals) should not be in direct contact with each other. This will minimize the chance that the magnet might break due to shock when the box is closed.
Two Magnets – This configuration is best used when a stronger bond is needed, and when the material is thick, creating a larger gap between them. Magnets can be inserted into die-cut paper boards, or they can also be mounted on a surface and laminated (or decorative designs, stickers or pads of some type can be placed on a magnet).