The Maxell NB-201 Stereo Neckbands Headphone is designed for comfortable listening, worn behind the neck and ears for portable music players. It features a frequency response of 20Hz-22,000Hz and is equipped with 30mm drivers, 32 ohms impedance, and a sensitivity of 100dB +/-3dB. With a rated input of 40mW and a maximum input of 100mW, it ensures quality sound output. The headphones include a soft-touch rubber 4' cord and a 3.5mm straight plug for easy connectivity.