Steel Framed Window Kits are designed for use with Type 4 and Type 12 Enclosures. Stainless Steel Framed Window Kits are for use with Type 4X Enclosures, however, they can also be used on Type 4 and Type 12, if additional corrosion protection is needed. Steel kits are constructed from heavy gauge and have an ANSI 61 gray polyester powder finish. Stainless steel kits are constructed from Type 304 stainless and have a brushed finish. Each kit includes a .25 inch (6 mm) thick polycarbonate window and gasket to ensure a tight, oil and water-resistant seal around the enclosure cut-out. Hardware and instructions for field installation are also furnished. UL Listed.