Genuine Hondabond HT (hi-temp) silicone liquid gasket. Remember to clean the part / bolt thoroughly before applying liquid gasket. Apply it as thinly and evenly as possible using a brush or putty knife. This really matters, it can make the difference between the sealant working or not working. If you do a nice neat job, it will seal and last. Wait one minute after applying the liquid gasket, then join the two surfaces.
For use in areas not requiring solid gaskets such as cylinder head covers