Brother HL-720 User Manual page 19

CHAPTER 1 INTRODUCTION
Do not subject the printer to strong physical shocks or vibrations.
Do not expose the printer to open flames or salty or corrosive gasses.
Do not place objects on top of the printer.
Do not place the printer near an air conditioner.
Keep the printer horizontal when carrying.
Do not cover the slots in the top cover.
CHAPTER 1 –7