The HP 212X is the high capacity range of toner cartridges, compatible with the Colour LaserJet Enterprise MFP M578dn and ever other printer we list on this page. The full product code of the black is W2120X and has an enhanced estimated page yield of 13,000 prints, more than twice that of the standard capacity.Purchasing genuine high capacity Hewlett Packard toner cartridges, like the W2120X, gives you the lowest price per page and doesn�t compromise print quality. Hewlett Packard guarantee the black 212X directly, so in the incredibly rare instance that there is a problem, you have the most knowledgeable support at your disposal.