Comfort Core:

Georgia Boot has designed this original Comfort Core® insert. Polyurethane materials have been utilized to create this energy return heel plug, which will make walking a more comfortable experience for you. It is unique because it stores energy as it’s compressed; as you lift your foot the energy is released. It gets even better… The Air Flow System feature of this insert continuously works to push air up through the footbed, which allows you to maintain cool, dry feet all day long.