Sennheiser CX300-B In-Ear Stereo Headphone (Discontinued by Manufacturer) Soft Silicone-Rubber Ear adapters in three different sizes Product Dimensions: 0.4 x 0.4 x 0.4 inches Powerful, bass-driven stereo sound Small and lightweight, Limited warranty - 2 years Frequency response of 18 Hz- 21 kHz