Hydrocollator Heating Units have been the first choice of therapists worldwide. These Heating units are known to last for years of use and can be used hundreds of times to provide up to 30 minutes of deep soothing moist heat for the relief of pain due to strained ligaments and muscle spasms. These are specially sized and shaped to clinically heat the wrist and hand. The E-1 holds four Hand HotPacs at the clinical temperature that makes moist heat an effective tool.