Per Bloomberg, 20% fentanyl tariff on China still applies and these categories may yet receive their own unique tariff, https://archive.is/jKupW

The exemption categories include components and assembled products, https://content.govdelivery.com/bulletins/gd/USDHSCBP-3db9e5...

  8471       ADP (Automatic Data Processing) Machines: PCs, servers, terminals.
  8473.30    Parts for ADPs: keyboards, peripherals, printers.
  8486       Machines for producing semiconductors & ICs: wafer fab, lithography.
  8517.13    Mobile phones and smartphones.
  8517.62    Radios, router, modems.
  8523.51    Radio/TV broadcasting equipment.
  8524       2-way radios.
  8528.52    Computer monitors and projectors (no TVs).

  8541.10    Diodes, transistors and similar electronic components
  8541.21    LEDs
  8541.29    Photodiodes and non-LED diodes
  8541.30    Transistors
  8541.49.10 Other semiconductors that emit light
  8541.49.70 Optoelectronics: light sensors, solar cells
  8541.49.80 Photoresistors
  8541.49.95 Other semiconductor devices
  8541.51.00 LEDs for displays
  8541.59.00 Other specialized semiconductor devices
  8541.90.00 Semiconductor parts: interconnects, packaging, assembly
  8542       Electronic ICs

Industrial-scale workarounds were developed for previous tariffs, https://news.ycombinator.com/item?id=43652823. Such loopholes will need to be addressed in any new trade agreements.