Power supply has protect function for over-voltage,overflowing,& short-circuit,full load & non-load voltage output varies <0.5V Halogen Cold Light Source Bulb Power:12v50w,12v75w,12v100w,15v150w,21v150w,24v150w,24v250w Voltage Extent AC:110V~220V±10% 50HZ~60HZ Input Power:<300w Illumination:15×10Lx-18×10Lx Colour Temperature:>3200K Bulb Service Life:50h