proflo pf42850 proflo pf42850 3" pvc roof drain with cast iron dome proflo proflo pf42850 features: constructed of cast iron ensuring durability and dependability covered under proflo's 1 year limited warranty high quality finish – will resist rust and corrosion through everyday use designed to drain water from a flat roof provides flow area exceeding 2" sq. contoured design allows for free flow and resists material build-up pvc drain body proflo pf42850 specifications: width: 12" height: 9-3/4" connection size: 3" connection type: fip