MG Chemicals 404B-340G, Contact Cleaner With Silicone, 12 oz., Aerosol, Case of 10MG Chemicals 404B 340G, Contact Cleaner With Silicone, 12 oz., Aerosol, Case of 10 The 404B Electronics Contact Cleaner with Silicone is a very fast drying contact cleaner. It is a plastic safe solvent cleaner that leaves a thin film of dry electronic grade silicone behind. The solvent system effectively dissolves oil and organic residues. The silicone provides lubrication, preventing wear and tear, as well as a layer of protection from oxidation and