Inkjet printer manufacturers, such as HP, Brother and Lexmark, highly encourage owners of their machines to use company-branded ink cartridges. Alternatively, shoppers can obtain a generic brand of inkjet supplies called RealJet. For example, people who own a Canon PIXMA MP500 should replace empty ink cartridges with the Canon CLI-8BK Black Ink Tank, per the company's recommendations. However, RealJet ink cartridges have compatibility across several printer brands. The benefit of using generic products is that shoppers may receive a significant discount at local and online stores, such as Walmart and Amazon.com, respectively. Some people question the quality of generics, like RealJet, but many people just need an economical way of printing out documents.