| Business | Phone |
| Clear Channel Engineering 9600 S Mason Montgomery Rd, Mason 45040 | (513) 398-5219 |
| Maxim Engineering 4457 Bethany Rd, Mason 45040 | (513) 770-3206 |
| Phoenix Design Ltd 8292 Winding Trail Pl, Mason 45040 | (513) 459-1469 |
| T Ec Engineering 214 W Main St, Mason 45040 | (513) 229-8829 |