AIR FILTER 79X37X151.5 mm COMPATIBLE WITH RIDE-ON MOWER ENGINE LAWN MOWERS LAWN MOWERS BRIGGS and STRATTON MODELS 31E877, 31L777, 31M977, 31Q677, 31Q777, 31S777, 31S877, 31S977, 31U977, 331707, 331777, 331807, 331877, 331977, 33M677, 33M777, 33M977, 33R777, 33S777, 33S877 PART NUMBER: 3-3921 ORIGINAL CODE: BRIGGS and STRATTON 793569 JOHN DEERE GY21055 MIU11511