Tri-ang Diesel Railcar
R.157 Power Car R.158 Dummy Car
 
There were four main versions of the Power and Dummy cars during the Tri-ang era.
| Type | Bogies | Logo | Number | Coupling | Roof | Note | 
| a Power | Power + X29 Coach | BR Lion | M79628 | Original Mk2 Open Type | Smooth | |
| Dummy | 2 X29 Coach | None | M79629 | |||
| b Power | Power + New X302 | BR Roundel | M79628 | Tensionlock | Smooth | 
 New non powered Bogie 
 | 
| Dummy | 2 New X302 | None | M79629 | |||
| b/2  
        Power 2nd Issue | Power + X302 | BR Roundel | M79628 | Tensionlock | Ribbed | Revised BR Roundel Ribbed roof | 
| 2 X302 | None | M79629 | 
 | |||
| c Power | Power + X302 | BR Roundel | Smaller M79628 | Tensionlock | Ribbed | Seating Unit fitted Smaller Buffers Darker Green | 
| Dummy | 2 X302 | None | Smaller M79632 | |||
| d Power | Power + X302 | BR Roundel | Smaller M79079 | Tensionlock | Ribbed | Yellow front panel added to Cab | 
| Dummy | 2 X302 | None | Smaller M79632 | |||
 
The four Dummy Cars
