No instructions but easy enough to figure out. I had to return them, even after trying a smaller size to help them fit more snugly around my heel. 5 with room for thick socks. If you are under 62 and 250 pounds I think it would be a solid pickup. They are surprisingly comfortable and quality for the cost! Keine Blasen an den Füßen. I love everything about these ear buds. There were a few things I was looking for in a headset:1. This microphone delivers a high quality sound and has headphone monitoring capability built in. About another quarter inch of strap on the larger sizes would be a good idea.