During a stay in physical rehab a few years ago the skin on my heel broke down. It is the nature of the beast that healing only restores to perhaps 75-80%. Thus being a back sleeper my heel was usually irritated and quite painful after only a few hours sleep. I tried propping my heel with extra pillows, epidermal restorative creams and lamb's wool sleeping boots with at best modest success. Although it is big and bulky, this device solves my problem, protecting my heel and allowing the best night's sleep I have enjoyed in years. It is firm enough to raise the heel a couple of inches off the bed. I bought the version with the cover that can be cleaned with alcohol wipes. I am quite pleased.