Next generation V3 series unit heater technology from Reznor. Glossy white cabinet finish with less visible hardware. Outside terminal strip and gas nipple; wire and pipe without removing panels, fan only without relays. New Tcore heat exchanger and single burner combustion system. Single stage gas valve, multi-try direct spark ignition with 100% lockout, vent flow pressure switch, resiliently isolated axial fan and motor, venter assemblies for low noise operation. Selection of either horizontal or vertical (concentric) combustion air vent kit is required for model UDAS. Vent cap required for model UDAP. Sold separately.