They tend to run away/flow from behind to front, especially when walking harder. Some soles have really good grip, others are really slippery.
Verified buyer

EzyShoes Walk - Easy to use grip devices for use with normal walking shoes. The structure works much like a set of snow chains for a car, with some sturdy metal rings at the sole for grip on ice and hard pack snow.
Grip devices harm several floor materials and can be dangerously slippery on stone and metal surfaces - only use them outdoors and stay aware of different materials. Always tread carefully in slippery conditions, despite using grip devices.