These corrosion-proof 18" CPVC Rainskirts are for the construction of exhaust ventilation systems. CPVC material compounds used in the manufacture of these duct fittings conform to Type VI, Grade 1 CPVC, Cell Class 23447 as described in ASTM D-1784. Overall dimensions are 22" diameter and 6" long. Socket depth is 2.5". Maximum service temperature is 200°F. NOTES: Fittings are triple bead welded. Pictures are to represent style of fittings only; actual color is light gray.