The newest model of Volt slippers is the Gen 4 Heated Slippers. One of the biggest key features that you can see is the addition of a zipper on the side that runs from the top opening down to the sole. This opens the entire side of the slipper up so that it is easy to slide on and off. It also has an added nylon pull tab on the back of the slipper to help ease the slipper on your foot. The wireless remote will help control the temperature settings that range from high, medium, and low. The durable but lightweight EVA rubber outsole allows you to take trips outdoors with the slippers on and still keep your feet toasty warm. The insole features memory foam that we added a little extra material to make this the most comfortable Volt Heated Slippers ever.