The Blue Series is our MERV 8 one-inch pleated residential air filter. Utilizing Kimberly-Clark's Intrepid Filtration Media, the Blue Series lasts three months and helps your air conditioning system perform at an optimum level. This puts less strain on your system and can result in long-term energy savings. With its wedge designed pleats and expanded metal reinforcement, the industrial-strength Blue Series filter is built to last. Filter Media The technology behind Kimberly-Clark Intrepid Filtration Media is thermally bonded continuous fibers to trap more dust, pollen, bacteria, animal dander and dirt. It is the same media utilized in commercial industries including hospitals, hotels, restaurants and commercial buildings.