Earbuds & In Ear Headphones. Set yourself on a path toward the clear Sound of Koss with high fidelity Koss Sparkplug in-ear headphones, a sound choice for listeners who like their music wherever they go. The Sparkplug's slow memory, soft foam ear cushions - made from hydrophilic, formed urethane - offer a custom fit with every listen. These in-ear headphones seal out ambient noise while delivering enhanced bass and clarity. Combined with your favorite music, the Koss Sparkplug in-ear headphones are the ultimate on-the-go accessory. Specifications: Frequency range: 10-20,000 Hz, Impedance: 16 ohms, Sensitivity: 112dB SPL/1mW, Cable: Straight, Dual Entry, 4ft. Finish: Black