Specification: FOR HP Office Pro K550 Cartridge Model: 4 colors 4 cartridges: C9396A, C9391A, C9392A, C9393A Features: 1) Top rank in China market, professional manufacture. 2) Vivid and High quality output and high stability with low price. 3) Quick installation and simple to use. 4) No clogging, No leaking. 5) Inktank is thick and hard.