Tungsten shoots like shit sometimes. Even if you buy from a source that's known to be good, sometimes you get a bad one that falls apart. The first set I ordered was never delivered, they punctured the tube they sent in and lost it. Revain quickly corrected the situation thanks to Amazon. Finally arrived, neatly cleaned of paint and sharpened. They were two different colors, which bothered me. When I cleaned them I found different colors/layers. So I used them as usual and had trouble keeping the ends on and one kept splitting so I sharpened the other end. He stopped splitting. With a current of only 130-150 amps, the ends would deteriorate every 5-10 minutes. With better luck I switched to a different electrode. When the amperage increased to 200, they could not withstand the pressure and kept leaving bits of tungsten in the workpiece. I didn't have a whole box, just three. But I wouldn't take more than three. I think they were old / possibly contaminated with moisture. I do not know. They definitely can't take the heat. I've had 3/32" tungsten bulbs that did a better job than 5/32" with far fewer problems.