| Business | Phone |
| Spence Engineering Svc 2000 Alameda De Las Pulgas, San Mateo 94403 | (650) 571-6500 |
| Spence Engineering Svc 3209 Verdun Ave, San Mateo 94403 | (650) 349-9425 |
| Aerospace Engineering 1875 S Grant St, San Mateo 94402 | (650) 378-2940 |
| Case Engineering Consultants 2318 Flores St, San Mateo 94403 | (650) 286-0560 |