Vendor may quote alternative gasket as option pricing during bid along with gasket technical datasheet; the use of alternative gasket is subject to Air Products approval.Spiral Wound: per A.2.2Biaxially-oriented silica-filled PTFE: per A.2.3Required Gasket Supplier for Gasket Codes [NS or TS]-150-LA-538 and [NS or TS]-306-LA-590 cleaned to Standard Clean (Class SC):