I actually sold them right after I posted that I got them, couldn't deal with the sizing. Photos don't really show it well, but the strap that's connected to the zippers has a snap that connects to the back of the heel. When unsnapped (to pull the zippers up and down), it makes a jingling noise, but it's quiet when it's connected to the heel snap. The strap itself is grosgrain (if I remember correctly), no noise at all.
9/16/16 at 4:34am