The Brother LC-223, LC-225, LC-227, LC-229 cartridges are single tank inkjet cartridges. That means for each color there is an individual cartridge. These cartridges do not have an integrated print head. The inner tank for the inks is protected by a housing that consists of two parts. At the cartridge´s front side the ink port protrudes from the housing. At this point the ink from the inner tank is flowing into the tubes inside the printer leading toward the print head. In the upper area of that side there is round opening in the front cap of the housing. Below that the air port is located.