Shutter Water Flapper Exhaust Y Pipe for Mercruiser OEM 807166A3

Exhaust Water Shutter Flapper for 4 Inch Y pipe used on Mercruiser.

Fits into the "Y" Pipe on most V-6 & V-8 engines to help prevent water from backing into the manifold and engine
swivel design and is sold in pairs

If your flapper currently has round grommets that hold it in, and a 4 inch Y-Pipe, then this is the correct flapper
If your current flapper is held in with square grommets, then you need MER807166A1

Replaces Mercruiser OEM # 807166A3

• Does Not Fit 4.3 Engines Originally Equipped with the 1 Piece Exhaust Manifold