The RM100 is fully loaded frame is heavy. To protect yourself and the equipment, mount the empty RM100 enclosure securely before plugging in the power and amplifier modules. The RM100 is designed for free vertical air convection cooling. We recommend at least one rack unit (1-3/4 inches) spacing between stacked units or forced air cooling of more densely stacked frames. If using forced air, seal frames and joints between frames with duct tape and use blank panels to seal any empty slots to avoid losing air pressure.