The clamp holds on tightly on your desk/other placement of choice. The thong part would definitely hurt of I wore them and the ankle part was super snug. Fit and finish are top notch, which is what you expect from a G Master lens and the price they demand. Kanten des Schuhs schneiden ein. Apart from that a perfect gift Love how comfortable these are. The light Work. Lol He says they are soooo comfortable! Great service, fast delivery & fantastic quality, would highly recommend The sound on all three are clear and rich - you get more bass sound from the 20 and 30.