These Main Jets are specifically designed to fit Stromberg 97, 81, 48, 40, LZ, and other compatible models. With a size of 0.043 inches, the set includes two jets that play a vital role in regulating the fuel flow within the carburetor, ensuring an optimal air-fuel mixture and engine performance. Installing these jets is convenient with the Genuine Stromberg jet wrench (9071K), providing a secure and accurate fit. It is crucial to select the appropriate jet size to achieve the desired fuel mixture for your specific carburetor and engine requirements.