These Main Jets, with a size of 0.046 inches, are compatible with Stromberg 97, 81, 48, 40, LZ, and other applicable models. The set includes two jets that regulate the fuel flow within the carburetor, ensuring an optimal air-fuel mixture and engine performance. Installing these jets is hassle-free using the Genuine Stromberg jet wrench (9071K), providing a secure and precise fit. It is crucial to select the appropriate jet size to achieve the desired fuel mixture for your specific carburetor and engine requirements.