I got an ice water delivery machine for shoulder surgery but they make them with pads that fit backs, too. They look like small picnic coolers and you fill them with water and ice (I used plastic bottles with frozen water). The cooling is gentle-not focused and harsh like ice cubes and no water or condensation moisture comes in contact with you or your wound site which is important to keep dry. I am glad I saved my machine to use now. You can set it for the time you want cold circulating through.