| Business | Phone |
| Advanced Finishing 1300 N Johnson Ave # 102, El Cajon 92020 | (619) 401-2200 |
| American Metal Processing Co 390 Front St, El Cajon 92020 | (619) 444-6171 |
| Precision Plating Inc 1488 Pioneer Way # 12-13, El Cajon 92020 | (619) 442-5066 |
| Molecular Metallurgy Inc 1770 Gillespie Way, El Cajon 92020 | (619) 596-7444 |