WPC, ST01c, 146x31mm, hollow, single size grooved, all weather resistant, 10 years guarantee. It is a safe, environmentally responsible alternative to traditional decks, conserving energy and resources. Not only does this save your time over the maintenance, but it will save you money as well. And Our company has been certificated of Quality Control System ISO9001 and Environment Control System ISO14001. The new material of Wood Plastic Composite has been tested by INTERTEK based on ASTM of USA testing criteria, by China NationalTesting Institute based on NationaStandard, certificated of European Conformity CE certificate and Green Building Material Certificate issued by Shanghai BuildingMaterial Testing Institute.