A sealed beam is a type of lamp with a parabolic reflector, one or more filaments, and a glass or polycarbonate lens sealed permanently together as a unit. Originally introduced for road vehicle headlamp service, sealed beams have since been applied elsewhere. Halogen sealed beam lamps have incorporate a halogen lamp within a quartz or hard glass envelope. Sealed beams utilize a parabolic aluminized reflector, and are thus known as "PAR" lamps. Round PAR lamp diameter is expressed in eighths of an inch, so a PAR56 lamp, for example, is 56/8" (i.e., 7 inches) in diameter. Other popular sizes are PAR30, PAR36, PAR38, PAR46, and PAR64. Rectangular PAR lamp size is expressed in millimeters, so a PAR200×142 is 200 mm wide and 142 mm tall. Sealed beams are available in a variety of nominal voltage ratings, most commonly 6, 12, 24, 28, 120, and 230 V. The actual operating voltage may differ from the nominal rated voltage; for example, "12 volt" sealed beam headlamps are meant for use in automobiles with typical line voltage of 13.5 to 14.2 with the engine running.
Country of Origin：Taiwan