The OEM Briggs & Stratton Lawn Mower Air Filter ensures proper fit and performance to maintain the life of your Briggs & Stratton engine. Many engine performance problems can be linked to maintenance issues such as stale fuel, a dirty air filter, fouled spark plug, and deteriorated oil. A great way to help avoid these problems is to perform an annual tune-up. Your outdoor power equipment's air filter provides superior protection against the destructive effects of dirt ingestion. This oval-style, pleated-paper Briggs and Stratton lawn mower air filter replacement provides superior protection against the destructive effects of dirt ingestion. for 550e, 550ex, 625ex, 725EXi Series with paper filter, this OEM part ensures proper fit and performance to maintain the life of your Briggs & Stratton engine.