The benefits of wet heat therapy over dry heat are well established for pain relief from arthritis, myofibrosis, back pain, muscle tension and spasms. Immerse in the Hydrocollator heating unit to heat, then remove, wrap in its sponge cover and apply to the treatment area. It provides up to 30 minutes of deep, soothing and moist heat. Profitable, each unit offers hundreds of treatments. Buy several to always have a loan for customers. We know they will love it and their treatment will progress much faster by stimulating circulation to help flush out toxins and increase the supply of rich, oxygenated nutrients available to damaged tissue.