This is the men's version. KSO stands for keep stuff out. they also have some where the mesh looking part is open. They have women's as well, of course.
This is what the Web site says about them:
"The typical human foot is an anatomical marvel of evolution with 26 bones, 33 joints, 20 muscles, and hundreds of sensory receptors, tendons and ligaments. Like the rest of the body, to keep our feet healthy, they need to be stimulated and exercised.
That’s why we recommend wearing FiveFingers for exercise, play, and for fun. Stimulating the muscles in your feet and lower legs will not only make you stronger and healthier, it improves your balance, agility and proprioception."
And, since Gary needs absolutely nothing, I thought about getting him some for his birthday... maybe. I'm still trying to figure out how I would measure his foot since it's not traditional sizing...