If you've heard of crampons you know that they're metal spikes worn on the feet for ice climbing and mountaineering. They're rigid, enabling climbers to support their body weight against frozen water and keep them from falling down while walking through the snow and ice. They're not designed for speed. The Nanospikes from Kahtooola serve a much different purpose, as they're designed to provide friction for runners and hikers who want to keep from slipping yet maintain their natural gate. You'll find 10 tungsten carbide teeth per crampon that are embedded in a plastic cleat that fits under your shoe or boot.
Stretchy, elastomer bands fit over your shoes and hold them in place. They're lightweight and comfortable, yet provide a great deal of traction in the ice and snow. The small teeth are strong enough that they won't get worn down while walking on concrete – so you can wear them even if the ice is sporadic. Those trails that were once off-limits until the spring are now accessible. And even if you're not up for winter exploring, they're a nice thing to have around when shoveling the driveway or walking through the neighborhood after a snowstorm.