If you are asking about the HF 110V welder, I stand by my earlier post. Not one complaint. It has worked great for everything I've used it for, though I have not attempted to weld anything thicker that two sheets at about 16 gauge. I did make a number of sample welds when I first got the unit (since it was used) and peeled them apart. Excellent penetration. Again, be sure the tips are filed and aligned. You can control penetration by how long you leave the power on - look at the diameter of the red spot that forms from the heat. It takes some trial and error to figure out what the right time is, but once you do, it works great.