PROFESSIONAL STONE HEATERS! Designed specially to heat massage stones, these CSA approved professional stone warmers are available in two sizes. The 18 quart heater is recommended for full body treatments and the 6 quart heater is the ideal choice for spa treatments or at home use. Its attractive stainless steel exterior makes it a visually pleasing addition to your therapy room. The temperature control dial features a "preheat setting" to quickly heat the water, as well as providing an "operating range" to help maintain desired water temperature. The heaters feature a Teflon-coated removable water reservoir with an easy-to-clean finish. All heaters include an instant read thermometer.