Square Exhaust Stainless Steel Flanges (Series SPFES) are manufactured in 304L and 316L stainless steel, ideal for strength and corrosion resistance. This exhaust flange’s material meets American Water Works Association (AWWA) C228 specifications. Notes:a. Flange material is stainless steel (to AWWA C228 specifications).b. Available in stainless steel 304L/316L. .pf-button.pf-button-excerpt { display: none; }