Reid's Super 80 Transmission Case is a direct replacement for the robust GM 4L80E transmissions and is designed to correct weak points and provide additional features over OEM castings. Super 80 cases are interchangeable in all 4L80E transmissions with just a few easy modifications in early-style models. Using a permanent mold casting technique, to increase the wall thickness, results in extremely strong, accurate, porosity-free castings that are SFI 4.1 certified; without the need for an external shield or blanket. The modular two-piece design allows this case to be used with all popular engines by simply changing bellhousings!