Grease like material containing an inert silica filler in combination with selected polydimethyl silicone fluids. Suitable for use in a moisture-proof seal for aircraft, automotive and marine ignition systems and spark plug connections, disconnection junctions in electrical wiring systems also in electrical assemblies and terminals. Used as a seal and lubricant for cable connectors, battery terminals, rubber door seals, switches and rubber and plastic O-rings and as an assembly lubricant for various metal-on plastic and metal-on-rubber combinations.