BCH Continuous Ink System for HP 940, HP 940 XL Cartridge, HP 8500, HP 8000 Printers, CISS, CIS Compatible with HP OfficeJet Pro 8500 All-In_One and HP OfficeJet Pro 8000 printer. Prefilled with premium high quality ink in cartridge and reservoirs Advanced TL series reservoirs auto-balance the pressure of the ink No mess, no hassel refill: just pour ink into reservoir.