Need HP 45 black ink? Match 51645A with your printer's required supply reference, then choose your quantity and condition: a single cartridge or two-pack, remanufactured or original HP OEM surplus.
View remanufactured single · View remanufactured two-pack
The cover image shows the remanufactured two-pack. Original HP OEM surplus options are separate listings with different condition and packaging details.
Which HP 45 option should you choose?
- One remanufactured cartridge: choose the HP 45 51645A remanufactured black single when you need one replacement.
- A remanufactured spare: the HP 45 51645A remanufactured two-pack contains two black cartridges. It does not include a color cartridge.
- One original HP cartridge: compare the HP 45 51645A original black single, OEM surplus. The listing states that condition varies by unit and is not selectable; packaging may vary.
- Two original HP cartridges: the HP 45 51645A original black two-pack, OEM surplus contains two original HP cartridges, not remanufactured replacements. OEM surplus does not guarantee that both cartridges are new or factory sealed.
Check current price, availability, packaging, and condition on the selected listing. Contact us before ordering if you require a particular condition. Buy a spare only if you expect to use it; a larger pack is not automatically better value.
Remanufactured or OEM surplus?
Remanufactured cartridges have previously been used and reconditioned for reuse. The original HP OEM surplus listings are a separate stock category, not a promise of new retail packaging. Do not apply one listing's condition to another item simply because both say HP 45.
Our guide to genuine and compatible ink terminology explains the broader distinctions. Use the exact product listing for the condition of the item you select.
Confirm the printer and full reference
Check your complete printer model, including any suffix, against the selected listing's compatibility information and your printer manual. Match HP 45 / 51645A rather than choosing by brand or black ink alone. HP 45 ink and HP 45A toner are different supplies; similar numbers do not establish compatibility.
Need help finding the details? Follow our guide to finding your printer model and cartridge number. If your model is not confirmed, ask before buying.
Buying black and color together?
Some HP 45 combo packs pair black with HP 23 color; others pair it with HP 78 color. Those are different color references and should not be treated as interchangeable. A printer's support for HP 45 black does not by itself confirm support for either color cartridge. Check both references and each quantity before choosing a combo.
Do you need MICR ink?
A separate HP 45 MICR listing serves applications requiring magnetic ink. The regular black cartridges linked above should not be substituted when MICR ink is required. Confirm the ink type required for your application before ordering.
Need help choosing?
Email support@generalinksupplies.com with your full printer model, cartridge number, and any condition requirement. For other supplies, browse HP printer supplies or follow our ink-selection checklist.
Ready to choose HP 45 black ink?
Once compatibility is confirmed, compare the remanufactured single, remanufactured two-pack, or OEM surplus two-pack for your preferred quantity and condition.