These Are A See Through Cartridge That Are Easilyefilled Through Theefill Hole On The Top Of The Cartridge. Simplyemove The Coloredubber Plug Inject The Ink Into The Hole Until Full And Put The Plug Back In. These Cartridges Come With Autoeset Chips Thateset Themselves After Youeinstall The Cartridge Into The Printer. Unlimited For Refill.