HP CM8000 Color Multifunction Printer series - Manual (Page 79)

3. To remove the staple cartridge from the cassette, push in at the arrow on each side and then pull
up to release the cartridge.
4. Insert the new staple cartridge into the staple cassette. Push the cartridge straight down until it
snaps into place.
5. Push the staple cassette straight into the slot.
ENWW Replace staple cartridges 71