Gauge Glass Gaskets in Non-Asbestos, Gylon® and Graphite. Gaskets are available in a range of sizes 1 through 9. Request a quote COUNTERFEIT GLASS ALERT! OverviewOverview Gauge glass gaskets are available for the full range of glass sizes 1 through 9. The most common gasket materials – Non-Asbestos, Gylon®, and Graphite – are in stock for immediate delivery.