Good product, make sure it is right for you
Firts, this is a good product.  I don't want to say they are a poor product, but I want to caution people depending on their needs.  My masks were not being held tight enough to my face, so I got these to hopefully tighten them.  They work as advertised in terms of how they function, and I'm sure that there are a lot of people who it would work for.  The mechanism for attaching them to the ear loops is much better than I thought.  The little "button" that slides into the loop is attached to fabric, not a rigid material.  The result is that there is no problem attaching them to most any thickness of ear loop material.  However,for me, it was too long.  I adapted them to work by looping it around on ear loop and attaching it to the other ear loop, essentially cutting it in half.  It is adjustable, but the shortest length is still 5 1/2 inches long, which I may have missed in the description.  That is way too long for my purposes.  I think part of the reason is that my ear loops are elastic, and when stretched far enough, the distance between them is much shorter.  My advice, measure the distance between the loops when you pull them back far enough for you.  Elastic loops may give more than you think.
Rating: 4 stars