Monitor II A.N.C. headphones utilise advanced active noise cancelling technology that blocks out the noise. With up to 30 hours of wireless playtime using active noise cancelling technology, or up to 45 hours without, you can keep the music going strong wherever you are. Featuring custom tuned 40 mm dynamic drivers, these headphones produce a signature sound only Marshall can deliver. MONITOR II A.N.C. KEY FEATURES Marshall signature sound ANC & Transparency mode 30 hours of wireless playtime Iconic & foldable design M-control button Multi-directional control knob