Dielectric grease helps insulate electrical contact points from moisture. It also keeps dust and debris out of the connection. Moisture buildup on plugs and sockets can corrode their contacts. Corroded parts may no longer make a good connection. Dielectric grease can be used on light bulbs to keep the sockets from corroding. It can also be used on spark plug boots, battery terminals and trailer connectors. If you notice electrical items not working, cleaning the contacts may help. Then, if needed, apply dielectric grease before reassembly. O'Reilly Auto Parts offers a wide range of products, including silicone paste and contact cleaner. Take a look at our selection and find products to protect your connections.