DJTECH DJH200 DJ Package Professional Over-the-Head DJ Headphones Padded adjustable headband to fit most heads Cushioned ear pads for comfortable listening sessions Closed-back design Swiveling ear cups for easy single-ear monitoring Driver Units : Dia 50 mm Cobalt Magnet Impedance : 60 Ohm +/- 5% Frequency Response: 18-20,000 Hz Sensitivity: 110 dB Max Power: 100 mw