SENNHEISER Headphones Headphone Accessory (003261) Rechargeable accupack 2.5V suitable for Audio port A1, E180, E90, Hde1030, HDI1029, HDI490, hdi91p1, Ir180, is200, is450, is490, is550, Ri100, Ri200, Set100, Set180, Set200 & Set90 Great for all your needs Easy to use