I have some other Fitsoks, and I was about to purchase but then I noticed this bit, "Coolmax polyester infused with SILVER."
Silver, typically nano-silver 'infused' products for anti-microbial properties, are harmful to marine and aquatic life -- and release into rivers, lakes and streams as they are washed over their lifetimes. They may also present health risks to humans, but thorough health and safety testing has not been conducted.
Personally, I prefer living rivers and lakes teeming with fish over germ-o-phobia and the worry of smelly socks. Smelly socks hasn't been so much of a problem for me that I would like to kill my surrounding waterways and sacrifice the health and vitality of my surrounding environment - in service of preventing some potential offending odor. That's just my opinion, however...
Fitsok - Please adjust your material sourcing to drop nano/micro-silver products. Massdrop, please make a better effort to avoid sourcing and selling products which are disproportionately harmful to our environment.