The Metalaire MDC is a direct digital control (ddc) diffuser. Unlike conventional diffusers tied to wall-mounted thermostats, this unit puts room comfort in the hands of the occupant through a handheld remote, says the company. A native BACnet® device, it is designed around a self-contained microprocessor mounted on the diffuser. The preprogrammed microprocessor measures and responds to room changes in heating or cooling modes. Installation costs are lower than conventional systems because there is no vav box or thermostat to install, the company says.