Update: I bought them in the summer and used them without any problems. However, when I went to wear them again now, I realized that the inner side of the strap has exposed metal parts that have rusted, causing irritation to the skin. They were stored in a place with controlled humidity throughout the winter. You will need a new pair every season.

Other than that, they are extremely comfortable. If you are between two sizes, prefer the larger one. Ideal for tired feet, swollen due to orthostatic or sedentary lifestyle. Their height relieves the waist. As for the width, it adjusts in three different scales. They do not slip and are very easy to clean/sterilize, even with the use of antibacterial cleaners or soap and water [Only for one season - 3 to 4 months].