Samsung SL-M4020ND-TAA - Manual (Page 65)

65 3. Maintenance
Replacing the imaging unit
When a imaging unit has reached the end of life, the machine will stop printing.
• Do not use sharp objects such as a knife or scissors to open the toner cartridge package. They might scratch the drum of the cartridge.
• If toner gets on your clothing, wipe it off with a dry cloth and wash clothing in cold water. Hot water sets toner into fabric.