Bright bar is produced from hot rolled bar by cold drawing (bright, tight tolerance, some work hardening), peeling (removes surface defects, larger sizes), centreless grinding (h6 to h9 tolerance, the smoothest) and polishing for decorative use.
Specify diameter, tolerance (h9, h10, h11 or a stated band), straightness, length, surface condition and grade. 303 is the standard for automatic lathes; 304 and 316 for general machining; 17-4 PH and 431 for strength; duplex for corrosion.
Bar is sold in 3 m, 4 m or 6 m lengths, or cut to length; ask whether ends are chamfered and whether ultrasonic testing is available for larger sizes.