Looking down at my finished Zapz footbeds you can see the contoured Dome that is auto-molded around the heel pocket that will stabilize and accommodate any heel shape narrow or wide. The insoles are actually two layers molded together give added comfort and support. The topcover is a soft, durable, friction-fighting material engineered to reduce blistering and wick away moisture. The lower piece is a firmer material to enhance balance, improve body alignment and provide for quick energy transfer.
After installing the Zapz Footbeds in my hiking boots Hals instructions were to wear the boots for a period of time allowing them to completely auto-mold to my feet then if I feel any discomfort I can have them re-heated and the fitting tweaked wherever there might be a problem.