This superior quality foam filter that provides the first line of defense against the destructive effects of dirt ingestion. It fits most 3.5-4.5 Gross HP Q45®, Classic™, Sprint™, Quattro™ engines with plastic air cleaner housing, and 450-600 Series™ 4.5-6 Gross Torque engines. Briggs & Stratton Genuine Part Designed specifically for our engines and can save on costly repairs while maintaining valuable warranty coverage.