Designed as a tank within a tank, the Cylindrical Gemini Dual Containment® Tank has dual walls to help secure chemical spills or leaks. The polyethylene tank construction is compatible with a variety of hazardous chemicals. This tank is ideal for water treatment or pharmaceutical usage, and it is built with a twist-off lid and pump mounting system to attach suction or dispense hoses. SKU 01-30135 and 01-30136 are not ANSI/NSF 61 Certified at this time. All other products are ANSI/NSF 61 Certified.