This under-cowl, inline fuel filter fits many Mercury and Mariner outboards replacing contaminated filters and is mounted under the engine cowl. The translucent plastic-cased filter allows you to check for fuel content and contaminants. Don’t let water moisture or other fuel contaminants rob horsepower from your engine. Filter those particles before they can get to your engine. Used on the 30-40hp EFI FourStroke outboard, the 4-cylinder (996cc) 40-60hp. EFI FourStroke outboards, the 75-115hp FourStroke (1.7L, serial No. 1B366823-2B094995), the 75-115hp FourStroke (2.1L, serial No. 2B094996 and above), the 150hp EFI FourStroke (1B905505 and above) and the 135-300hp. Verado outboards.