... Compact design Low noise Dynamic Compact Semiconductor Fan Heater, Industrial Electric Air Heater, CSL 028, 150W,250W,400WCompact designLow noiseDynamic ... and provides an evenly distributed interior air temperature in enclosures with electric/electronic components. The heater is connected ... accordance with UL508A Compact Semiconductor Fan Heater, Industrial Electric Air Heater, CSL 028, 150W,250W,400W