Devices capable of withstanding voltage and mechanical stress between conductors installed at different potential levels or between conductors and grounding components. There is a wide variety of insulators, each with different shapes. Although the structures and appearances of different types of insulators vary significantly, they are both primarily composed of insulating parts and connecting hardware.

Insulators are specialized insulating components that play a crucial role in overhead transmission lines. In earlier years, insulators were commonly used on utility poles, gradually evolving to include many disk-shaped insulators hanging 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 should not fail due to various mechanical and electrical stresses caused by changes in environmental and electrical load conditions, as their significant function is to ensure the integrity and longevity of the entire line's operation.