Replace the ink in your HP DeskJet or Envy printer with the HP 305 6ZD17AE#301 Black & Tri-colour Ink Cartridges.Ideal for home or office use, this 2-cartridge pack will give you up to 120 black ink pages and 100 Tri-colour pages.HP Instant Ink Save up to 70% on ink with HP's Instant Ink service. When your printer is running low, it automatically orders more ink cartridges, so you don't have to order them yourself. The service works on how many pages you print, not how much ink you use. You can choose from a range of monthly page plans, and unused pages roll over to the next month. The price includes ink, shipping and cartridge recycling.Compatible printers:- HP DeskJet 2710- HP DeskJet 2720- HP DeskJet 2300- HP DeskJet Plus 4100- HP ENVY 6000- HP ENVY Pro 6400