PRODUCT TYPE VENTING FOR GAS HEATERS, COMPATIBLE WITH PRODUCT TYPE DAYTON INFRARED TUBE HEATERS, OPENING HEIGHT 4 IN, OPENING WIDTH 4 IN, MOUNTING TYPE FLANGE-MOUNT, VENT DIRECTION HORIZONTAL OR VERTICAL, VENT LENGTH 9 IN, VENT DIAMETER 4 IN, VENT SIZE 4 IN, VENT TYPE SIDEWALL OR ROOF VENT ACCESSORY, MATERIAL GALVANIZED STEEL, OUTER DIAMETER 4 IN, OVERALL LENGTH 9 IN, INCLUDES VENT ELBOW, STANDARDS UL LISTED