1.      Smooth internal and external surface, so small friction.

2.      Free from combustion

3.      Well insulation: 500V DC and more than 100 megohm of resistance.

4.      High corrosion and aging resistance, so over 50 years of lifetime.

5.      Well impact strength and machanical intensity, so high voltage pressure resistance and tensile property.

6.      Light weight, easy installation, and 40%-60% more efficient than cast iron ones, so low cost of construction.

7.      No smell and no poison.

8.      Special additive which products free from strange smell mice and bugs like, so avoiding been bitten by them.

9.      Low consuming, so enviromental protection.