HQRP 10-Pack Foam Air Filter for Briggs & Stratton Classic, Sprint, Quattro 450, 475, 500 Series 3.5-4.5 HP Lawnmower Engine Coaster HQRP&reg; 10-pack Air Filter Foam Element Replacement + HQRP&reg; Coaster; Air Filter is used on 3.5 - 4.5 HP Q45, Classic, Sprint, Quattro, and 450 - 600 Series engines with plastic air cleaner. Replaces Briggs and Stratton Air Filter Foam Element # 698369; 100% Compatible with Original filter. 2 weeks DOA replacement warranty!