This metering diaphragm ensures fuel and stable engine operation, featuring model HS81 for reference, providing reliable carburetor performance, consistent engine response, and smooth operation for small engine applications. Replacement-friendly design supports installation, referencing model FS85, delivering accurate fuel metering, stable combustion, and dependable performance during extended use of outdoor power equipment. Engineered for durability, this diaphragm uses model FS120 for identification, maintaining carburetor operation, consistent fuel flow, and reliable engine function for efficient landscaping and gardening tasks. Designed to restore fuel metering, this diaphragm uses model HS81 for identification, supporting consistent carburetor function, engine starts, and dependable performance in small engine applications. Fits for metering diaphragm compatible with ST HS81, FS85, FS120, 4229, 121, and 4700 models, providing accurate fuel, consistent carburetor performance, stable engine operation, starts, and reliable operation for small engine equipment.