In search of safe magnets to use in the classroom or in a children's environment? Hero Magnets to the rescue! Chunky size with the magnets completely encased in plastic. Strong display magnets help you get, and stay, organized. Great for whiteboards, filing cabinets, fridges and more. Each set includes 3 bi-color magnets. Flip them over to see a different bright color. Big Rings are 1.375"D x .50"T and hold 13 pieces of paper. Big Buttons measure 1.375"D x .50"T and holds approximately 10 pieces of copy paper. Big Blocks measure 2"Lx1"Wx.50"T and 20 pieces of paper.