Gemstar's Stronghold cases are the toughest roto-molded cases on the market. Stronghold cases provide the ultimate protection in the most rugged terrain. These cases are double-walled and construction from polyethylene. That means thicker corners and stress-free walls making this the strongest case you can buy. These cases are suitable for heavy-duty applications, such as reusable shipping containers and instrument housing. These cases have been used by the US military, all around the world, in all types of conditions. All hardware is stainless steel, and each case comes standard with a pressure relief valve. All sizes are available in a wide range of colors and with an option for further customization. Custom tooling options are also available to meet your size requirements.