AISEN (Pack of 4 Pre Filter Air Filter for Briggs & Stratton 3.5 to 6 HP Engine Lawn Mower 271933 491435 491435S 493537 493537S Replacement manufcturer part no. 271933 491435 491435S 493537 493537S For Briggs & Stratton 112200 12A800-12T899, 128700-129799 and 92200 series 3 to 5 HP horizontal, 3.5 to 6 HP Quantum and 6 HP vertical small engines Qty: 4 x pre filter