Devices capable of withstanding voltage and mechanical stress between conductors at different potentials or between conductors and grounding components. Insulators come in a wide variety, with diverse shapes. Although there are significant differences in the structure and appearance of different types of insulators, they are all composed of two main parts: insulating components and connecting hardware.

Insulators are specialized insulation components that play a crucial role in overhead transmission lines. In earlier years, insulators were predominantly used on utility poles, gradually evolving to include many disc-shaped insulators at one end of tall, high-voltage transmission towers. These are designed to increase the creepage distance. Typically made of glass or ceramic, they are referred to as insulators. Insulators must not fail due to various mechanical and electrical stresses caused by changes in environmental and electrical load conditions, otherwise, they would not serve their significant purpose and could harm the entire line's service and operational lifespan.