| Business | Phone |
| Blue Arc Elec Engineers Inc 14811 N Kierland Blvd # 200, Scottsdale 85254 | (480) 361-5450 |
| Cemi 7631 E Greenway Rd, Scottsdale 85260 | (480) 991-1085 |
| Polyphase Engineering 14469 N 54th Pl, Scottsdale 85254 | (602) 569-0668 |
| Donald Aadland Engineering Po Box 340, Scottsdale 85252 | (480) 946-5165 |