Here is an MTH 40-4000 O Z-4000 400W Dual Control Transformer from 1998. This monster is specifically designed to operate modern-era locomotives and equipment.
Features:
Sine Wave Output
(2) )-22 VAC, 165 VA Variable Outputs
(1) 14V, 1.5-Amp Fixed-Voltage Output
(1) 10V, 1.5-Amp Fixed-Voltage Output
Digital LED Displays For Realtime Voltage & Amperage Readings of the Variable Outputs
Microprocessor Controlled, Smart Operation During Short Circuit Conditions & Expendable Design
(2) Bell Button For Tracks 1 & 2
(2) Horn/Whistle Button For Tracks 1 & 2
(2) Direction Buttons For Tracks 1 & 2
(2) Program Buttons For Tracks 1 & 2
On/Off Power Switch
Large Power On LED Indicator
Large Overload LED Indicator
12 Amp Resettable Circuit Breakers On Track 1 & 2 Variable Outputs
4 Amp Resettable Circuit Breakers For Fixed Outputs 10V & 14V
Expansion Port For Future Upgrades
Internal Cooling Fan For Low Operating Temperatures
Compatible Power Source For All O Gauge, AC-Powered Locomotives
Rugged ABS Construction

This item has been graded per TCA standards C-6: Very Good based on visual appearance. This item displays scratches and scuffs across the plastic exterior. The upper shell is cracked, as well as the inside of the right hand throttle shell. The left channel bell button is missing the cap. The original box is not included. The instruction manual is not included. This item has been inspected by our repair shop. Please see the attached picture for inspection details and additional operation information. Overall condition is Very Good.

Condition: Very Good (C-6)
Operational Status: See Description
Original Box: No

Manufacturer: MTH
Model Number: 40-4000
Years Manufactured: 1998 – ????
Road Name: **** No Road Name

Scale/Era: O Modern
Model Type: Control & Electrical

The SKU for this item is 5961029.

Product Id: 11415165