Unique One-Piece Housing:_x000D_The smooth one-piece sealed housing, constructed of heat-resistant cross-linked polyethylene (XLPE), features our patented filter-to-housing interface (US PAT 9440175). Its innovative design minimizes the total number of parts, making for an easy installation. A large, clear sight window allows for hassle-free filter inspection, without having to disassemble your system. Its auxiliary air inlet can be used with an optional Dynamic Air Scoop (PN 50-70034S) to capture cool air directly from the front of the vehicle or can be closed with an included plug if desired.