R3F panel radiators are manufactured in the USA from cold rolled steel and consist of two panels with three sets of fins. The panels are finished in a gloss powdercoat, and are available in many standard colors and over 100 optional colors. These panels are made in lengths from 2-0 to 29- , and heights from 3 to 29. Standard piping connections are 1/2 NPT for inlet and outlet piping, and 1/8 NPT for vents (3/4 NPT inlets and outlets are available by special order). For more complete R3F specifications, please refer to the Runtal technical pages.