304 and 304/L (UNS S30400 UNS S30403) are austenitic alloys of stainless steel bars. These alloys are the most familiar and most frequently used alloys in the stainless steel family. The L in 304/L refers to a lower carbon content to allow for greater corrosion protection when welding. Available shapes: Hexes, Rounds, Square In order to keep pace with the never-ending demands of customers, we are involved in offering a wide range of Stainless Steel 304 Round Bar. Nearly all grades of stainless steel are stocked in round bar, including 302, 303, 304/L, 304H, 309/S, 310/S, 316/L, 317/L, 321, 321/H, 347, 347H, 410, 416, 420, 440C, 17-4PH, Duplex 2205 and Alloy 20.