XPOWER AP-2500D Air Purification System PF-23 Stage 2 Pleated Media FilterXPOWER Stage 2 Pleated Media Filter for XPOWER AP 2500D Air Purification System Regular filter replacement ensures maximum efficiency and helps to prevent cross contamination. Sturdy, high capacity filters effectively capture airborne particles, and won't "blow out" under heavy use. The PF 23 Pleated Media Filter is compatible with the XPOWER AP 2500D Portable HEPA Air Purification Systems. This durable pre filter prolongs the life of subsequent