This intake manifold is designed to work with 19mm carburetors in 4-stroke machines. It will fit many 50cc to 110cc engines in ATVs, Dirt Bikes, and Scooters. Commonly used in conjunction with a PZ19 carb. Opening is 20.1mm, the mounting holes are 4.8mm and 5.5mm apart centre to centre respectively. Same as 20A9191 with a less pronounced bend.