Comfortable,Flexible and Stable. Sounds Good... Stays Put. Superior Sound Clarity. Plantronics noise-canceling microphone reduces background noise so you can be heard clearly Ultimate Flexibility. Pivoting, flexible boom allows for optional placement of the microphone Comfort Fit. Flex Grip design produces an exceptionally stable, comfortable fit and allows for one-handed placement in the ear; no interference with eyeglasses or sunglasses In-Line Convenience. Conveniently answer or end calls from the in-line button; button also activates voice dialing 3.5mm female to 2.5mm male adapter included