The My Cartridge Toner Cartridge Replacement for HP Printers (4 Pack) is a set of compatible toner cartridges designed for use with various HP printer models. Specifically, this product is compatible with the HP Color LaserJet Pro MFP M477fdw, M477fnw, M477fdn, M377dw, M452dn, M452nw, and M452dw printers. These cartridges are designed for laser print technology and come in a sleek black color. The 4-pack ensures that you have an ample supply of cartridges on hand for your printing needs, making it a convenient and cost-effective choice for HP printer users.