Canon's exclusive Think Tank ink management
system, a feature on the i9100 Photo Printer as
well as on several of its other printers, is
designed to help eliminate ink waste and reduce
printing costs. It allows you to replace only the
color that runs out, rather than the entire
cartridge. A unique low-ink sensor alerts you
when ink levels are low, so you can drop in a new
tank. Ink cartridge compatible with the following
printers: BJC-8200, i860 Series, i900D, i9100,
i950 Series, i960 Series, i9900, PIXMA iP4000,
S800, S820, S820D, S830D, S900 and S9000.