The SMARTFLEX complete multilayer piping system for the transfer of automotive and aviation fuels, biofuels and hazardous fluids was installed in Knoxville and Nashville, Tennessee. The SMARTFLEX system has many international approvals and is used and approved by all the major international petroleum companies, in response to whose needs it has been conceived, developed and successfully launched into the market. SMARTFLEX has a vast range of pipes and fittings. All products are available in a wide variety of sizes and configurations making the system suitable to various kinds of installation. The key material employed in the production of SMARTFLEX is high-density polyethylene (HDPE-PE100), a material with high durability and working benefits to the user. Moreover, HDPE can be a more cost-effective solution than more traditional materials such as metal. All SMARTFLEX primary piping consists of a multi-layer composite wall lined product pipe that combines the excellent mechanical properties of HDPE with the low permeability and high resistance to hydro-carbons of a new class of polymers used in the lining material and creates a level of hydro-carbon compatibility unattainable by other fuel pipes available on the market today.