Spun aluminum, supported on brass rods. Cast aluminum with half inch NPT at bottom, plus solid brass locknut for mounting. Porcelain medium base with silicone lamp gasket. No. 18AWM rated 105C. Super TGIC thermoset polyester powder coat paint, 2.5 mil nominal thickness, applied over a titanated zirconium conversion coating; 2500 hour salt spray test endurance rating.UL Listed to U.S. and Canadian safety standards for wet locations.