N2 Air Filter Replaces Briggs & Stratton #(s) 399959, 4101, 491588, 491588S, 5043B Briggs & Stratton #(s) 399959, 4101, 491588, 491588S, 5043B, 5043D, 5043H Length: 5-1/4" Width: 4-1/2" Warranty: This part shall be free from defects in material and workmanship under normal use and service for three-months from the date of purchase You can return this item (for any reason) if you ask for a return within 30 days of receiving your order and have not installed your product