These lightweight Gear Head HQ4750GRN Noise Isolating On-Ear Headphones were designed to be comfortable, for hours of listening enjoyment that will inspire you to work longer and play harder. The innovative headphones feature custom-shaped 40mm drivers that deliver Dynamic Bass Response for improved audio performance. The design combines plush ear cups and metal headband technology to create a comfortable seal to isolate you from ambient room noise. Tangled cords are a thing of the past with Flat Cable Technology. You might wonder why they ever made them round at all.