Protects sensitive electronic equipment from problems caused by AC line voltage irregularities such as brownouts, sags, and over-voltage conditions. Using an autotransformer, the M-8x AR corrects for these deviations to deliver a stable 120V output (+/-5volts). Best for professional live sound, instrument rigs, tube amps, recording studios (install in equipment closet) and critical applications where stable voltage is essential for audio quality and equipment safety. It is the best choice for protecting sensitive digital equipment from damage and malfunctions caused by brownouts, sags, and other line voltage irregularities. Also increases lifespan of connected equipment.