Dow Corning 112 high consistency valve sealant off-white is a one component, stiff grease, silicone compound that is used for lubricating and sealing applications that require mechanical and temperature stability such as valves, bearings, locks, and o-rings. It is thermally stable, non-melting, low volatility, and is resistant to oil, water, alkalis, dilute acids and most chemicals. - Dow Corning 112 high consistency valve sealant is a grease-like compound containing an inert amorphous silica filler in combination with selected polydimethyl silicone fluids. This stiff, non melting silicone material is used primarily as a valve lubricant and sealer.