Trimmer potentiometers are usually made from carbon, wirewound metal wires, thin-film or cermet. Because carbon versions are made of low cost materials their output stability is inferior to the other materials. Metal wire trimmers have high output stability but they lack a smooth output due to the wiper jumping from one wire to the next. Thin-film trimmers have the smallest operating resistance range. Cermet trimmer potentiometers have superior temperature characteristics and heat resistance while maintaining a wide resistance range.