| Present Location | Boness |
| County Location | Falkirk |
| Designed For | BR |
| Build Location | Wolverton |
| Built by | BR |
| Diagram number | 99 |
| Lot number | 30702 |
| Type | RMB |
| First Number | 1866 |
| Later Numbers | M1866 MACLAYS, 99811 |
| Present Number | 1866 |
| Current Livery | BR Crimson Lake and Cream |
| Gauge | 4ft 8 1/2in |
| Wheel Arrangement | 4-w bogies |
| Original Underframe | Yes |
| Original Bogies/Wheelsets | Yes |
| Additional Notes | P 1983 by SRPS, at Falkirk till 1988 then at Perth till 1990. Vacuum brake, dual heat. Good. Branch service. Fluorescents as later (BR) addition. Recently repainted and refurbished. |
| Owner | Scottish Railway Preservation Society |
| External Structural Condition | Good |
| Internal Structural Condition | Very Good |
| Underframe Condition | Good |
| External Finish | Very Good |
| Internal Finish | Very Good |
| Degree of External Originality | As built/last Passenger rebuild (BR or before) |
| Degree of Internal Originality | As built/last Passenger rebuild (BR or before) |
| Degree of Underframe/Running Gear Originality | As built/last Passenger rebuild (BR or before) |
| Degree of External Authenticity | Good |
| Degree of Internal Authenticity | Good |
| Degree of Underframe Authenticity | Good |
| Rarity | Many |
| Historical Importance | Some Interest |
| Storage | Secure Open |
| Operating | Yes |
| Survey Date | 21/09/2002 |
| Surveyor | Trevor England |
| Photo Date | 19/05/2012 |
| Photo by | Steve West |
| At Risk | No |
| Date Record Last Updated | 01/01/2025 |
