Insert label sheet into typewriter and type call number as usual. For best results, we recommend plastic-base carbon or fabric ribbons. Place supplied clear overlay on top of typed label, position on book spine and then seal it permanently with a heating plate or tacking iron. Labels can be removed with heat, ordinary lighter fluid or typewriter cleaner. Rounded die-cut corners. Each set contains 50 sheets of 20 labels and 50 sheets of 20 transparent overlay shields. Total of 1,000 labels and 1,000 shields per set. 1"W x 1-1/2"H. Wt. 1 lb. Ships ground.