The 1590Z155BK is a Type 4X diecast aluminum enclosure designed for rugged electronic instrument applications requiring watertight protection. It features a two-piece tongue and groove construction with a one-piece silicone rubber gasket that provides protection against dust and water ingress, meeting IP66 design standards. The enclosure measures 8.70 inches in length, 4.72 inches in width, and 3.58 inches in depth (less lid), with a wall thickness of 1.18 inches, and includes an internal mounting shelf for component installation. Four recessed stainless steel machine screws secure the lid into tapped holes, with self-captivating lid screws that are threaded upon first installation. The unit is cUL and UL listed to NEMA 4X standards (UL 508A, File #E65324) and is available in black powder-coated finish. This enclosure is ideal for repetitive opening and closing applications, outdoor installations, and environments requiring robust protection against environmental contamination.