Compact under cowl fuel filters for smaller Mercury, Nissan, and Tohatsu outboards Removing fuel contaminates will protect sensitive engine parts and keep your outboard running in top shape. Sierra's inline fuel filter elements deliver effective filtration while maintaining fuel flow. These compact inline filters are designed as the last filtration point in the fuel line and can be easily installed under the cowl of Mercury outboards. Key Features Inline design allows filter to be installed easily along fuel hose Compact design for under cowl installations Compatible with many 1999 and newer 4hp and 5 hp 2-cycle outboards and 1999 or new 4hp, 5hp and 6hp 4-stroke outboards Compatible with many 2005 and new 8hp and 9.9hp 4-stroke outboards and 2008 and newer 15hp and 20hp 4-stroke outboards See our Engine Parts Selector to confirm this filter is right (or to find the correct one) for your outboard.