These are from surplus stock. They are new, never used. It will function properly, however it will not be in nice pretty packaging. You will have to move a small screw from your existing printhead and put it on this one for its circuitry to be recognized once installed. See YouTube for details.They are sold without a warranty as I have a lot of customers who purchased this and try to resurrect an old printer and return a used printhead when they can’t get their machine working, so I'm not offering returns on this item even though it’s new and are forced to sell it sold as is.
This printhead will work with the following models:

PhotoSmart 6510

PhotoSmart 6515

PhotoSmart 6520

PhotoSmart 6525

PhotoSmart 6510 e-All-in-One

PhotoSmart 6510 e-All-in-One B211

PhotoSmart 6510 e-All-in-One B211A

From a small bit of research this should work along with these models, but please double check my research before buying as I've only used this on the 65xx series:

Deskjet 3070A

Deskjet 3520 e-All-in-One Printer

Deskjet 3521

Deskjet 3522

Deskjet 3526

OfficeJet 4610 e-All-In-One Printer

OfficeJet 4620 e-All-In-One Printer

OfficeJet 4622 e-All-In-One Printer

PhotoSmart Plus e

I've been told that the 55xx printers only use 3 ribbon connectors, I do not know if the print head will work with the 4th port being left unconnected.

PhotoSmart 5510 e-All-in-One

PhotoSmart 5511

PhotoSmart 5512 e-All-in-One

PhotoSmart 5514 e-All-in-One Printer B111h

PhotoSmart 5515 e-All-in-One Printer

PhotoSmart 5520 e-All-in-One Printer

PhotoSmart 5522 e-All-in-One Printer

PhotoSmart 5524, Photosmart 5525 e-All-in-One