Beginning on February 8th the 25% tariffs on Chinese steel and aluminum will now also include derivative components made from those metals such as staples, nails, tacks, and cable wiring, according to a proclamation from the White House issued on January 24, 2020. The proclamation included a statistical basis for the increase noting a dramatic surge of imports for these derivative components since the announcement of steel and aluminum tariffs were announced in 2018.
NYT: Trump Expands Steel Tariffs, Saying They Are Short of Aim