This means that you'll be able to search for NAICS codes directly (if that's your jam). We'll do the math; let's make better data on public procurement together.
Railroad Gates; Flasher Lights; Block Signals.
Semaphore Flag Signals.
Possible NAICS Codes
811210 – Electronic and Precision Equipment Repair and Maintenance
335132 – Commercial, Industrial, and Institutional Electric Lighting Fixture Manufacturing
334220 – Radio and Television Broadcasting and Wireless Communications Equipment Manufacturing
332322 – Sheet Metal Work Manufacturing
325413 – In-Vitro Diagnostic Substance Manufacturing