Product Includes: 2 x Replacement Filter 4 x Carbon Booster Filter Product Description: Carbon Booster Filter It is compatible with Holmes HAP242-NUC, which could be cut to fit other models ,such as HAP2400, HAP242, HAP412, HAP422, HAP424, HAP1200, HAP706 or HAP716. Compatible with Bionaire Units: BAP260, BAP815, BAP825, BAP9200, BAP9700, BAP520. Holmes Units: CAP531-U, CAP529-U, HAP240, HAP242, HAP412, HAP422, HAP424, HAP706, HAP716, HAP9240, HAP9242, HAP9412, HAP9414, HAP9422, HAP9424 PLEASE NOTE: This is not a Holmes OEM product. The Holmes brand names and logos are the registered trademarks of their respective owners. Any use of the Holmes brand name or model designation for this product is made solely for purposes of demonstrating compatibility.