This is Permatex Anaerobic Flange Sealant. It's designed for sealing close-fitting machined steel or iron assemblies that have less than a .015-inch gap. That includes parts like transmission pans, timing covers, transfer and transaxle cases, and water pumps. It can withstand temperatures up to 300 degrees F and flexes with flanges that move when the vehicle is in motion. Usually, those parts rely on paper, rubber, cork, or preformed gaskets for sealing. With this sealant, you have no more leaks from all that stuff! For more information, click here.
Photo credited to SummitRacing.com
Video credited to Permatex.com