| Advent Systems | 630-279-7171 | 477 Wrightwood Ave | Elmhurst | IL | 60126 |
| Areawide Cellular | 630-420-0000 | 1032 E Ogden Ave | Naperville | IL | 60563 |
| Auto Alarm Center | 630-969-4434 | 419 Ogden Ave | Downers Grove | IL | 60515 |
| Bromann Mark Engr | 630-668-8998 | 201 S Naperville Rd | Wheaton | IL | 60187 |
| Cam Co Securty Eqpmnt | 630-556-3110 | 4th & Rhodes Ave | Big Rock | IL | 60511 |
| Cohn Bert Associates | 630-530-5522 | 188 Industrial Dr | Elmhurst | IL | 60126 |
| Continental Instrument Corp | 630-469-3535 | 286 Elm St | Glen Ellyn | IL | 60137 |
| Control Electronics Corp | 630-483-0337 | 6859 Hemlock St | Hanover Park | IL | 60103 |
| Denning Electronics Corp | 630-920-1488 | 136 Burlington Ave | Clarendon Hills | IL | 60514 |
| Folger Adam Co | 630-739-3900 | 16300 103rd St | Lemont | IL | 60439 |
| Gage-Babcock & Associates Inc | 630-368-0660 | 600 Hunter Dr | Oak Brook | IL | 60521 |
| Midco Inc | 630-887-1800 | 16 W 221 Shore Ct | Burr Ridge | IL | 60521 |
| Mobile Tel | 630-469-4100 | 420 Roosevelt Rd | Glen Ellyn | IL | 60137 |
| Mobile Tel | 630-231-9440 | 2 N 520 Prince Crosng Rd | West Chicago | IL | 60186 |
| Mobile Tel | 630-232-0190 | 1489 E State St | Geneva | IL | 60134 |
| Mobile Tel Ltd | 630-941-7788 | 17 W 454 22nd | Oakbrook Terrace | IL | 60181 |
| Monarch Fr Prtctn Inc | 630-293-0063 | 645 Joliet St | West Chicago | IL | 60185 |
| Spring Valley Presbyterian Church | 630-736-1000 | 2155 Wildwood Ln | Hanover Park | IL | 60103 |
| Woodham Radio Service | 630-759-9575 | 267 N Naperville Rd | Bolingbrook | IL | 60440 |
| Woodham Radio Service | 630-378-0638 | 110 W Boughton Rd | Bolingbrook | IL | 60440 |
| Ziebart Tidy Car Downers Grove | 630-968-8082 | 2101 Ogden Ave | Downers Grove | IL | 60515 |
| Ziebart Tidy Car Naperville | 630-355-9555 | 1580 W Ogden Ave | Naperville | IL | 60540 |
