Compound insulator series are made up of the three parts: Epoxy resin glass fiber rod, silicom rubber sleeves, and metal parts ( including through wall conductive rod). Production technology: Metal pressed and connected method to integrate once time with silicom rubber sleeves, which will promote the security of the insulators and the productive efficiency. Merits: High strength, small volume, light weight, and good looking appearance. 1. Compound insulators have high electrical performance, silicon rubber sleeves are the good hydrophobe and have water floating capacity, heavy pollution resistance, can prevent flashover due pollution. It can work on the severely polluted sites without special clearing. 2. High mechanical strength, the anti-bent and anti-pull capacity of the glass fiber rod is several or eventen times of the porcelain type. 3. Compound insulators are generally small, and light( about 1/5 and 1/10 respcetively ), easy to carry and install.