| Owner: | Martin Marietta Materials Incorporated |
| Type: | Gondola |
| AAR Class: | GT: Open top car, having high fixed sides and fixed or hinged ends and solid bottom, suitable for unloading on dumping machines only. |
| AAR Type: | J301 |
| Detail Info: | Gondola, Load Limit: 185,000 and greater, Flat Bottom, Inside Length: 36-48ft |
| Plate: | B |
| Max Gross Weight: | 286000 |
| Load Limit: | 232200 |
| Dry Capacity: | 2480 |
| Ext L/W/H: | 42' 0" / 10' 6" / 11' 1" |
| Int L/W/H: | 37' 1" / 9' 2" / 7' 4" |
