G4 is a one part moisture cured polyurethane very similar to varnish. It comes in different viscosities determined by the application. G4 is sold as pond sealer but was originally made for sealing wood.
G4 is a one part moisture cured polyurethane very similar to varnish. It comes in different viscosities determined by the application. G4 is sold as pond sealer but was originally made for sealing wood.