This product is applied to high voltage power line service. And have features of good gydrophobicity, anti-ageing, anti-leakage trace and electric erode proof , tensile strength and bending strength, strong mechanical strength, shock resistance good quakeproof and brittle failure proof , light weight, easy to installation, and the installation iutline of top and base are the same size with porcelainpin type, they can exchange to use each other.