This is a pretty high quality roller bike trainer! let me tell you. My noise testing was not accurate, but is uniform in method. Cant seem to find any shoes, sneakers, dress shoes that are comfortable for several hours. Dislike: The covering or imitation leather flakes off in ~ 1 to 2 years. I bought mine on sale at a bike shop. It connects by itself, you can use one at a time. Used it for 9 hours on a single charge! The shoes were in prestine condition, even coming with the hanger they use at the store. I hope I don have to edit this comments in the future, but as far as i am concern, this headphone is perfect like was expecting.