Rebuild Kits for PAPAILIAS 4" 150# Flanged End Series FIF Sight Flow Indicator with Tempered Borosilicate glass lenses and Expanded PTFE elastomer seal gaskets. All Rebuild kits are supplied with the following[Qty: 2] Tempered Borosilicate Glass Lense[Qty: 2] Expanded PTFE Elastomer Seal Gaskets[Qty: 2] Compressed Non-Asbestos Inorganic Fiber Lens CushionsAll instruction must be read and understood thoroughly before attempting any installation, operation or maintenance. Failure to follow any instruction could possibly result in a malfunction of the sight flow indicator or glass breakage with resulting sudden release of pressure causing serious personal injury and/or property damage.ALWAYS WEAR SAFETY GLASSES WHEN INSTALLING OR SERVICING OR OPERATING A SIGHT FLOW INDICATOR.