The key indicators are as follows:

- Low skin effect: It is recommended to choose litz wires or multi-strand thin wires.

- Low dielectric loss: Enameled wires with polyurethane or polyesterimide paint can be selected.

- Self-adhesiveness: It helps to reduce the impregnation process.

Common temperature resistance grades are as follows:
- 130°C (Class B): It is a general-purpose type, widely used in household appliances and small motors.
- 155°C (Class F): Applicable to industrial motors and transformers. It has better heat resistance compared to Class B.
- 180°C (Class H): Mainly used in high-temperature working environments such as high-temperature motors, transformers, etc.
- above 180°C (Class C): It is suitable for special electronic devices in extremely high - temperature and high - pressure environments, such as motors and transformers in the aerospace and nuclear industries.