The Therm-ic Smartpack 1200 with TrimFit is no longer available. It was discontinued in 2017.
Please view our current selection of Therm-ic boot heaters.
There is no need to replace your current insoles with this system. Because the TrimFit is designed to work with your current insoles. The Therm-ic SmartPack 1200 batteries are unique because they use Lithium-ion battery technology which is lighter in weight than AA or nickel metal hydride batteries. And Lithium-ion batteries weigh almost half of what the other system batteries weigh and are smaller in size so they fit better on the back of your boots.