Commercial Quality 5052 or 5083, 3 and 4mm Marine Grade Alloy Built To Survey Requirements if Necessary. Stainless Steel 316 Sheet 1.6 to 3mm. Built to VMR or Coast Guard Specifications. Recreational boating requirements are also catered for. Our tanks can be built to you dimensions and requirements and to our standards. Contact us with your needs and we can give you a quote.