The Lubricant | Vacuum Grease (30 g) is a high-vacuum silicone grease used to lubricate and seal ground glass joints, O-rings, and vacuum stopcocks on laboratory glassware and vacuum systems used in distillation and extraction. Vacuum grease reduces gas permeation through glass-to-glass joints and prevents seizure of ground glass connections exposed to elevated temperatures and solvents. This 30 g tube provides a sufficient supply for regular maintenance of all glass joints on a VTA or UIC distillation system. Compatible with glass, PTFE, and metal vacuum components.