The device makes a high quality impression. I use the device to operate in the motor home a TV and Satreciever, or at times a battery of devices to charge, in which I have no 12V Addapter. It works so far everything properly. Picture and sound are the TV clearly and show no interference from the voltage conversion. The fan had with me so far not start, it was very quiet. I also like the security alerts in case of overvoltage, low battery voltage and reverse polarity. (Works) Good is also the possibility of relatively easy to switch between 2 different 12 V connecting cables. (Car socket and directly to the battery) The only drawback: I find the connection cable should be considerably longer! (About 50 cm long)