The cylinder heads are machined from aluminum billets. The uranium metal produced was in the form of derbies, ingots, billets and fuel cores. In the UK, extrusions are made from billets of dia. There are four types&colon; "ingots", "blooms", "billets", and "slabs". Structures are made from metal billets, reducing weight. Camp Pendleton Ca, with only 50 unfilled billets on its first day. Construction of Barksdale Field began in 1931, when hangars, runways, and billets were built. Enschede where the guilder billets were printed. Demand began dropping for passenger billets on the steamship lines. Dried heartwood billets are nearly white and are suitable for decorative use. For example, Nismo sells parts such as unground cam billets, performance cams, pistons, etc. Also ArcelorMittal Kryviy Rih specializes in manufacturing of sections, angles, strips and billets. The FY 2021 budget allocates 10,000 civilian and military billets to the USSF. There were about 33 women who were the first assigned to these sea billets. Operational billets are open to men and women.