The KZ HD9 HiFi In-Ear Sports Earphone lets you enjoy your music in the highest quality possible. It comes with a dynamic vocalism principle that gives you clear and powerful sound, while the 3.5mm connectors provide a strong connection. The KZ HD9 with a professional level of noise performance. The correct wear effectively isolates the outside world as high as 20Db+ noise. It has a frequency response range of 20-20000Hz and is resistant to 32Ω, so you can hear every note in perfect clarity. It also features active noise cancellation to keep out distractions and allow you to focus on your music. Noise Isolating design and the silicone earbuds allow you to fully immerse into your music without any other distractions It comes with a built-in microphone, so you can take calls without having to stop what you're doing. The KZ HD9 HiFi Sports Earphone comes with no warranty.