Insulators are composed of ceramic components and upper and lower metal attachments bonded together with adhesive. The contact area between the ceramic component and metal attachments is padded with an elastic gasket. The bonding areas of the ceramic components feature structures such as sandblasting, knurling, and grooving for mechanical strength, anti-loosening, and anti-twisting properties. The ceramic surfaces are evenly coated with white glaze, while the metal attachments are painted with gray magnetic paint. The main structures of the ceramic components of insulators include hollow partition (penetrable) and solid (non-penetrable) structures. The combined bonded pillar insulators are generally solid and non-penetrable. This latter structure reduces maintenance and testing work compared to the former. Insulator ceramic components come in two shapes: with or without棱, with the multi-ridge shape increasing surface distance and electrical performance over the single-ridge shape. All products except for the outer bonded pillar insulators to be phased out are multi-ridge. The internal bonding structure, due to the metal attachments being glued into the ceramic holes, increases the insulation distance and improves electrical performance, while also reducing the space required for installation. However, as internal bonding is不利于 increasing mechanical strength, insulators with higher mechanical strength requirements should use combined bonding (i.e., the upper attachments use internal bonding, and the lower attachments use external bonding).