1-piece. Hi-heat bakelite body for temperatures up to 150 deg. C. Will stand temperatures up to 250 deg. C. on intermediate use. Switch built in/open screw terminals. Turn knob is nonremovable. Overall length: 1-5/16". Bushing length: 3/8" x .27" x 11/32". Wire recommended for specific temperature as follows: AWM (plastic) wire, 105 deg. C/221 deg. F. AF (asbestos) wire, 150 deg. C/302 deg. F. SF (silicone) wire, 200 deg. C/392 deg. F. UL listed.