JEGS Big Block Mopar & Hemi windage tray is made from glass filled nylon and features re-usable silicone gaskets molded on the top & bottom of the tray. This tray is made using the same materials as many modern production engines. This combination windage tray & gasket increases HP, can be hand washed with soap & water and re-used over & over again. Future engine service is simpler since you won't have to scrape off the old gasket and replace it each time the oil pan is removed. Available in two sizes - up to 3.75" stroke or up to 4.15" stroke for all Big Block Mopar (383/400/413/426W/426 Hemi/440) engines.