Epson UltraChrome HD ink is a professional quality printing ink that can be found inside the T7603 magenta cartridge. The Whale range of ink cartridges are purpose built to work with an Epson SureColor SC-P600 wireless, large format printer. Using a large format printer like the SC-P600 is a little more involved than the average household printer and is certainly likely to cost a little more but the results are totally worth it. If you own one of these incredible printers you know how important it is to stay fully stocked with fresh ink cartridges because running out part way through a large print can be catastrophic. Buy the Epson T7603 magenta on its own or stay fully stocked by buying the full set.