I just want to say that it is the best inverter I ever seen because I see the back up of my friends and relative’s invertor they discharge after some time but my inverter stay last long, my inverter is 10 years old as you can see in the picture but it is still working well however it cannot be opened till now , if any of my friend ask me to buy which inverter , I simply recommend the luminous inverter to him bacause now I can trust on this brand on behalf of my experience