HQRP 2-pack Secondary Filters for Hoover Anniversary Self-Propelled U6485900 U6485900B UH50000 UH50005B Bagged Upright Vacuums Coaster HQRP&reg; Two Windtunnel Secondary Filters + HQRP&reg; Coaster; This filter are located behind the grill in the bottom of bag compartment, protects the motor from dirt particles; Replaces Hoover Secondary Filter part # 38765019 / 38765-019, 38765023 / 38765-023; Measures 5" x 2 3/16" x 3/8" with a rectangle notch; 100% Compatible with Original filter. 2 weeks DOA replacement warranty!