This pump sends fuel to the carburetor when the engine is started. Size (Approximate): Outside Diameter - 0.75 inch (19 mm), Inner Diameter - 0.59 inch (15 mm), Height: 0.55 inch (14 mm). Walbro WPV12 type - Compatible with Walbro caps such as the WA, WT, WY, WYL, WYJ, WYK, WYB WYP, and are the most commonly used type. (There are engravings on the body of the cap). The type of carburetor above may also not fit depending on the type of model. Please check the size of the pump.