Through hole resistors are used to reduce the flow of electrical current within a circuit. As fixed resistors, they have predetermined values (voltage range compatibilities), unlike variable resistors where the voltage range values can be adjusted.
Through hole resistors are constructed from metal film for general usage or carbon film for devices that require high tolerance. They have long, pliable leads that are inserted (either automatically or manually) into holes in printed circuit boards.
Through hole resistors are used in the automotive, telecommunication and medical equipment industries. They are most suitable for larger circuit boards and prototyping projects where no soldering is required.
The most common types of through hole resistors are wire wound and axial components: