The dimplex 15k w oil free column heater with patented oil free technology its patented fin design creates a balance of radiant and convected heat thermostatically controlled with frost protection an on off switch and choice of two heat settings lighter than equivalent output oil filled column radiators and its oil free design makes them easier to recycle and kind to the environment it also has an integral cable tidy and easy glide castors independently tested and carries beab approval for extra