Sony MDR-NC500D Digital Noise Cancelling Headphones

Groundbreaking technology, for your listening pleasure. The innovative MDR-NC500D Headphones use Digital technology to more accurately reduce stress-inducing noise from planes, trains and buses while providing the high-quality Audio expected from Sony. For extra-long use, a built-in Lithium-Ion Battery is included, as well as two AA batteries. The combination of bridging internal battery with 2 AA can provide up to 28 hours of listening pleasure. Driver Unit : 40mm diameter, dome type Frequency response : 5 - 24, 000Hz Impedance : 40 Ohms at 1kHz (on) Selectivity : 3 distinct noise-canceling modes for use in three accoustically different environments (Airplane, Bus, office) Sensitivity : 102dB/mW (on) Closed, dynamic headphone Cord Length (Approx.) : 1.5m -L-type Stereo mini plug, .5m stereo mini plug; Weight (Approx.) : 6.9oz/195g (including built in battery) Battery Type : DC1.5V- 2 size AA battery, DC 3.7V -built in rechargeable Lithium-ion battery Battery Life up to 16 hours (with built in fully charged battery) or up to 28 hours (with fully charged built in battery and 2 fresh AA batteries) Includes Carrying Case, AC Power adaptor for charging internal battery, Two AA Batteries, Inflight plug adapter, Unimatch® plug adapter, Connecting cord x3 (.5m stereo mini, 1.5 type stereo mini, cord with battery case), Startup guide, and Sony Warranty card