The Hi-E 40H is a medium efficiency pleated filter specially constructed for use in systems involving elevated operating temperatures. The perimeter frame on the Hi-E 40H is constructed of 24 gauge aluminized steel. The pleated element is supported downstream by a 24 gauge expanded aluminized steel face guard to ensure stability of the media pak at elevated temperatures. The filter media is ¼” thick, high-density ultra-fine fiberglass reinforced by a woven fiberglass mesh. The Hi-E 40H is constructed to operate at 400 degrees F continuously and may be subjected to temperatures up to 450 degrees F for short durations of not more than 10 minutes. This filter is offered in 2 inch and 4 inch widths.