The HP JC81-09882B Unit-3K Finisher Staple Cartridge is a staple cartridge for a printer finisher, used to staple documents as part of the finishing process. It is identified by the exact HP part number JC81-09882B.
The HP parts list for the LaserJet Managed MFP E72525-E72535dn includes this cartridge. Its Unit-3K designation distinguishes it as the listed finisher staple cartridge for that parts reference. It is intended for the finishing unit rather than general-purpose office stapling.