The HP 45 Large Black Ink Cartridge 51645A is a genuine original ink cartridge designed for HP printers, specifically HP Deskjet models. This cartridge is in black color and utilizes inkjet print technology. It is a single unit cartridge that is compatible with HP printers and was manufactured in Singapore. The product is sealed and comes as one cartridge, despite being expired. It falls under the category of printer ink cartridges and is suitable for use in printers, scanners, and other computer-related devices.