Air filter replacement. Fits Briggs and Stratton 12.5-20 horsepower twin cylinder. l-head vertical shaft engines. Also fits series 402700, 421700 with precleaner foam filter wrap Briggs and Stratton model 271271. Replaces Briggs and Stratton air filter model 394019. Size 9-5/8” long x 3-3/8” wide x 2-1/2” high.