I recently flew to Switzerland for a summer vacation where I took this Tideline sunglass retainer. I wore them all over with ease. I even went paragliding and hit a building! I had to be carried down a mountain to a car that then took me 100ft to a wheel chair, down two cable cars and into and ambulance and then into the ER! Through all of that I knew my sunglasses were safely around my neck! I didn't have to worry where they went, if they flew off or if they were broke! I knew they were right there around my neck doing exactly what you want them to! Just staying put! Chums makes a quality product! And I know this because it's now been Swiss tested by an American. Keep up the great work!