Boss Tech Products, Inc. BTP-HAT-BLACK Stereo Tech Knit Hat with Built-In Handsfree - Retail Packaging - Black Beanie style knit hat is made of 100% acrylic knit stitching with a polyester lining that allows for comfort, warmth, breathability and flexibility Will fit a wide range of head sizes and will return to its original shape after each use Sewn in stereo speakers are more comfortable for all day wear than traditional in-the-ear stereo headsets. Listen to music, or make phone calls with the inline microphone, answer and end call controls, and a volume control. Stereo headset can be unplugged or hidden away when not in use. Included collar clip keeps 3+ foot long cord secure.