The t post electric fence insulators are used for the steel t post, the t post electric fence insulators need to clamp on the t post insulator tightly, so it have special design. please see the following pictures. based on the different installation direction, there are 2 types of installation methods.  these t post electric fence insulators will keep the polywire wire or polyrope around 3″ or 5″ away from the steel t post.