ZS-Solid Core Post Insulators;ZSX-Catanary Post Insulators;C-Operation Post Insulators;W-Anti-pollution Type;Numerator after frist"-"-Rated Voltage;Denominator-Catilever Failing Load;N-Torsion Failing Load;L- Ukufakwa Okuphansi Nokuphezulu konke kune-Screw Hole;Idatha ngemva kwesekhondi"-"-Ikilasi Leleveli Yokungcolisa.