This specification covers rolled shapes (wide flange shapes, angles, etc.), having a specified minimum yield strength of 50 ksi (345 Mpa), intended for use in offshore structures. Commonly available Class A, Class B, and Class C beams refer to degrees of fracture criticality as described in API RP 2A-WSD, with Class C being for the least critical applications.For special critical applications, specifications for Class AAZ shapes may be specified, by agreement, using Supplement S101.