DELIVERS COMBINATION OF PASSIVE & ACTIVE NOISE REDUCTION (ANR); SOFT VINYL\, CLOSED CUSHIONS CREATE A SEAL AROUND THE EAR; ACTIVE NOISE REDUCTION CIRCUITRY BUILT DIRECTLY INTO THE EAR CUPS; NOISE REDUCTION CIRCUITRY CAN BE TURNED ON & OFF WITH A FLIP OF A SWITCH; EXTRA-SOFT\, PADDED HEADBAND; COMPLETELY COLLAPSIBLE-IDEAL FOR TRAVEL ; FREQ RESP: 40 HZ-20 KHZ; IMP: 32_; SENSITIVITY: 90 DB/MW; 4-FT SINGLE ENTRY\, STRAIGHT CORD; REQUIRES 2 AAA BATTERIES FOR APPROX 30 HOURS OF CONTINUOUS PLAY; INCLUDES 2-PRONG AIRLINE ADAPTER