The ET-600 is a planar heater developed by Kawai Corporation for use at high temperatures. The insulator uses specially-developed mica ceramic paper, which can withstand high heat ranges up to 930ºF (500ºC). This model offers a maximum watt density of 109 W/in 2 (17 W/cm 2 )—astonishing for a planar heater. The heater is suitable for places where it must be exposed to sharp rises in temperature. It can also be modified for complex shapes, such as holes, notches, or curls.