These Main Jets, with a size of 0.044 inches, are designed to fit Stromberg 97, 81, 48, 40, LZ, and other compatible 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 straightforward using 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.