| Business | Phone |
| Primary Instruments Inc 9553 Vassar Ave, Chatsworth 91311 | (818) 993-4971 |
| Simco Electronics 19804 Nordhoff Pl, Chatsworth 91311 | (818) 773-9750 |
| Eagle Eye Calibration 9960 Canoga Ave # D8, Chatsworth 91311 | (818) 993-0055 |
| Eagle Eye Calibration Lab Inc 9950 Canoga Ave, Chatsworth 91311 | (818) 993-1655 |
| Metrology West 9960 Canoga Ave # D8, Chatsworth 91311 | (818) 718-1799 |
| Micro Quality Calibration 20743 Marilla St, Chatsworth 91311 | (818) 701-4969 |