Esab Shield-Bright 308L X-TRA description: Shield-Bright 308L X-tra was designed for welding type 304L stainless steel but can be used for types 301, 302,and 304 steels. It may also be used successfully for welding of types 321 and 347 stainless steel. Service conditions should not exceed an approximate of 750F (399C). Shield-Bright 308L X-tra was designed for welding in the flat position and for horizontal fillet welds with flat to concave beads with excellent slag removal.