This specification covers two grades of a premium aircraft-quality, corrosion-resistant steel in the form of bars, wire, forgings in the solution heat treated condition, and forging stock. Product covered by this specification is limited to a nominal 6.00 inches (152.4 millimeters) and under diameter or maximum cross-sectional dimension between parallel sides (thickness), unless the product is tested in the response to H1000 condition (see 3.5.1.2 and 8.7). When product is tested in the H1000 condition, the product is limited to 8.00 inches (203.2 millimeters) and under diameter or maximum cross-sectional dimension between parallel sides (thickness). Stock for forging may be of any size.