| Owner: | Union Pacific Railroad Company |
| Type: | Box Car |
| AAR Class: | XM: Box car for general service equipped with side or side and end doors. |
| AAR Type: | B414 |
| Detail Info: | Unequipped Box Car, Inside Length: 49' to 59', cushion draft gear/underframe, Sliding doors, inside width 9ft 6in and over, Door opening 10ft to 11ft |
| Plate: | C |
| Max Gross Weight: | 220000 |
| Load Limit: | 158100 |
| Dry Capacity: | 5355 |
| Ext L/W/H: | 57' 3" / 10' 8" / 15' 6" |
| Int L/W/H: | 50' 6" / 9' 6" / 11' 3" |
| User Notes: | ex-CIRR 2022 exx-IATR 4258 exxx-AHW 4258 nee-MTW 4258 |
