Wiseco W5678 Top End Gasket Kit Fits: Yamaha WR400F (92mm bore) 1998-00, YZ400F (92mm bore) 1998-00 Contains all the necessary gaskets and O-rings to rebuild your top end Wiseco gasket kits are made from the highest quality materials and engineered by Wiseco to insure compatibility with Wiseco pistons and crankshafts Each gasket kit is sourced in-house to find the most reliable, high quality suppliers available Ensures a critical seal and superior durability that meets and exceeds OEM specifications