The insulators are made by gluing ceramic parts and upper and lower metal accessories with an adhesive. The contact area between the ceramic part and the metal accessories is padded with an elastic pad. The gluing parts of the ceramic parts are structured with sandblasting, knurling, grooving, etc., to enhance mechanical strength, prevent loosening, and twisting. The ceramic parts are uniformly coated with white glaze, and the metal accessories are coated with gray magnetic paint. The main structure of the ceramic parts of the insulators consists of two types: a hollow partition structure (penetrable) and a solid (non-penetrable) structure. The combined adhesive-mounted pole insulators are generally of the solid non-penetrable structure. This latter structure reduces maintenance and testing work compared to the former. The main structure of the ceramic parts of the insulators can also be a hollow partition structure (penetrable) or a solid (non-penetrable) structure. The combined adhesive-mounted pole insulators are usually solid non-penetrable. The ceramic parts have either multi-angled or less-angled shapes, with the multi-angled shape increasing the surface distance and having better electrical properties. All products except the gradually phased-out external adhesive-mounted pole insulators are multi-angled. The internal adhesive structure, due to the metal accessories being glued into the ceramic part holes, increases the insulation distance and improves electrical performance, while also reducing the space occupied during installation. However, as internal adhesive is not beneficial for enhancing mechanical strength, insulators requiring high mechanical strength should use combined adhesive mounting (i.e., the upper accessories use internal adhesive, and the lower accessories use external adhesive).