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.
Modification of Equipment: Valves
Possible NAICS Codes
811310 – Commercial and Industrial Machinery and Equipment (except Automotive and Electronic) Repair and Maintenance
811210 – Electronic and Precision Equipment Repair and Maintenance
238220 – Plumbing, Heating, and Air-Conditioning Contractors