These are great for the back of envelopes. The envelope is used to place boxtops for education clippings in. The envelope with the magnet on the back can be placed on the fridge until you want to mail what you have collected. Remove the magnet from the back of the envelope and place in the mail to the address on the envelope.
I purchased 700 magnets to use on the back of a pad of grocery lists. The magnets are so strong that I cut them into 3 pieces and they will hold a pad of 25 sheets measuring 3 1/2 by 8 1/2 inches. Great product.
The Business card size magnets will work fine in lieu of the 1" x 2.5" write on magnets I needed. I will cut in half width wise place address labels with names typed on them so I can use them to do a visual organizational chart of the people on our team.