Koss Sleek Colors Noise Isolating In-Ear Headphones, RUK30B: * Noise-isolating in-ear stereophones * Cushions come in small, medium and large for a comfortable fit * Flat, 4" tangle resistant cord with 3.5mm plug * Available in multiple colors * Frequency response: 15-20,000Hz * Impedance: 16 ohms * Sensitivity: 110dB SPL * Color: blue