Watertight - Thick Wall - Diecast Aluminum Enclosures Heavy Duty (1590Z Series Natural) Key Features: Rugged, diecast aluminum alloy (tough yet easy to machine), electronic instrument enclosure. Two piece “tongue & groove” construction with a one piece silicone rubber gasket provides protection against access of dust and water. Ideal for repetitive opening and closing. Four recessed stainless steel machine screws secure lid into tapped holes. Easy to wall mount using "through box - blind hole" construction, outside of gasket protection. Lid screws are self captivating (lid holes are threaded with the first installation of lid screws). Designed to meet IP66. North American Mark of Safety - cUL & UL listed. Certified to NEMA 4X standards (UL508) - File #E65324 (NOTE: Except for 1590Z140, 1590Z235 & 1590Z164) Painted versions are painted inside and out with a tough powder paint. Choice of satin black or smooth grey (RAL 7001).