I am a surgeon who received these with my order of surgical loupes. Many surgeons use the original Chums to keep their loupes snugly in place while operating. I was excited to see these sleekly designed stainless steel orbiters as an alternative to the typical cotton retainer. The ends fit my loupes just fine, and the orbiter is very lightweight. Unfortunately, even at the tightest setting, a gap remains between the orbiter and my head. As a result, my loupes can jiggle around and slide down my nose while I’m operating. Chums, please make a shorter version of the adjustable orbiter! I would have loved using these but had to fall back on the original retainer model.