HP 2820 - Manual (Page 220)

Replacing and recycling supplies
To install a new HP print cartridge or imaging drum, follow the instructions that are included
in the box that contains the new supply, or see the getting started guide.
To recycle supplies, place the used supply in the box in which the new supply arrived. Use
the enclosed return label to send the used supply to HP for recycling. For complete
information, see the recycling guide that is included with each new HP supply item. See
HP LaserJet printing supplies for more information about HP's recycling program.
204 Chapter 13 Managing supplies ENWW