Hicool Bluetooth Headphones, Hicool K1 Iron Man in-Ear Sport Stereo Wireless Earphones Bluetooth 4.1 Technology: The powerful audio decoding system gives you strong performance, making higher transmission and lower consumption. The stereo speakers ensure music more sense of space, delivering you vigorous and remarkable sound. Excellent Sound Quality: The high definition stereo noise cancellation reduces the loss of sound, eliminating the surrounding noise and solving the problems of play delay and staccato, making the bass deeper. The high fedility stero speakers endow music better sense of space, delivering you more vigorous and beautiful sound. Anti-perspiration Design: The ABS and PC material blocks your sweat trouble, effectively preventing the headphones from damaging. You can heartily asperses your sweat and paasion. Unlimited music, endless sport. Strong Compatibility: The powerful audio decoding system enables you to pair with All Kinds of Digital Products, no matter what brands and regardless of what systems. As long as you have bluetooth enabled devices, you could connect it easily and quickly. You are able to connect two devices simultaneity as well. High Definition Noise Cancellation: Adopted deep stereo noise cancelling technology, eliminates the surrounding noise and improves the quality of voice communication, making sound more clear and melodious. Deeper bass and brighter treble offers you more layered and dynamic music.