| Business | Phone |
| Black Horse Engineering 459 N Larch Ave, Elmhurst 60126 | (630) 279-3160 |
| Cooney & Assoc 359 E Webster Ave, Elmhurst 60126 | (630) 834-0754 |
| Henderson & Bodwell Consulting 124 W Diversey Ave, Elmhurst 60126 | (630) 834-9406 |
| Kelburn Engineering 851 N Industrial Dr, Elmhurst 60126 | (630) 930-5700 |
| Levin & Assoc 188 W Industrial Dr 116, Elmhurst 60126 | (630) 530-8181 |
| Norsman Packaging 172 N York St, Elmhurst 60126 | (630) 530-4373 |
| Pgc Consulting 224 N Geneva Ave, Elmhurst 60126 | (630) 941-1419 |
| Sterling Engineering 977 N Oaklawn Ave 300, Elmhurst 60126 | (630) 516-1010 |