The Lexmark C750 supplies are designed to provide exceptional value, reliability & outstanding print quality. C750 supplies offer an easy front-loading design with a simple, intuitive user interface. In addition, Lexmark has streamlined the number of necessary supplies products from prior offerings. With the C750, the only additional supply product necessary beyond toner cartridges is a simple waste toner container. Return/ Prebate cartridges are sold at a discounted price vs. the price of regular cartridges in exchange for the customer's agreement to use the cartridge only once & return the cartridge to Lexmark for recycling once it's empty. All toner boxes ship with prepaid postage labels for customers to return their empty cartridges for recycling.