I bought these .040" electrodes for thin sheet metal work combined with a gas lens set for welding. For the purpose I bought them for and the price so far I have been excellent. These tungsten electrodes, used for welding in the 20-50 amp range, sparked brightly and stayed sharp throughout the project being welded (roughly fairly flat to minimize the area of the arc). They also did a great job of maintaining a sharp, "hard" feel that allowed me to move the sweat puddle with ease. Can you buy better electrodes with lanthanum coating? sufficient for most welding applications within the appropriate amperage range of this diameter? a pack of premium electrodes.