#9005 and #9012:

Imagine the towerman throwing switches and radioing trains from his elevated perch

opening top hatches

to couple between the A units of your big diesel to get a really long power plant (couplers are not remote control)

The Trainz SKU for this item is P12398720

TCS 30207 HO Pennsylvania Railroad Interlocking Tower Kit DwDetails-0.07-0.07-6.65-3.65-3.65-2 #9005 and #9012:This is a TCS 30207 HO Pennsylvania Railroad Interlocking Tower Kit Condition: Factory New (C 9) Operational Status: Functional Original Box: Yes (P 9) Manufacturer: Train Control Systems Model Number: 30207 MSRP: $19. 99 Scale Era: HO Scale Model Type: Building Kits The Trainz SKU for this item is P12552176. Trainz Product Id: 12552176