Studio closed back 'phones with 40mm drivers, 1,600mW power handling, 15-24,000Hz. Two cables The M-Series ATH-M40x professional monitor headphones are tuned flat for incredibly accurate audio monitoring across an extended frequency range. Your studio experience is enhanced with superior sound isolation and swiveling earcups for convenient one-ear monitoring. Engineered with pro-grade materials and robust construction, the M40x excels in professional studio tracking and mixing, as well as DJ monitoring. Available in Black and Matte Grey.