| 1 | ZTT | Transporttechnik Zeller KG | | A | TRAFFIC |
| 2 | ZTTU | Zhytomyrske Tramvaino-Troleybusne Upravlinnya | City: Zhytomyr | UA | TRAFFIC |
| 3 | ZTTX | Trailer Train Co. | added 4/1966; eliminated 1/1992 | | NAKINA |
| 4 | ZTTX | Trailer Train Co. (FM flat cars for general service. These cars are equipped with 15 stake pockets per side, total 30 stake pockets) | 10/1966-10/1968 | | NAKINA |
| 5 | ZTTX | Trailer Train Co./TTX Co. (flat cars equipped with 30 stake pockets, 15 per side; for transporting long poles) | 4/1970-7/2000 | | NAKINA |
| 6 | ZTTX | Trailer Train Co. | added 4/1966; eliminated 1/1992 | | NAKINA |
| 7 | ZTTX | TTX Co. | added 1/1992; 1/1994-7/2005 | | NAKINA |
| 8 | ZTTX | Trailer Train Co. | added 4/66; eliminated 1/92 | | NRHS |
| 9 | ZTTX | Trailer Train Co. (FM flat cars for general service. These cars are equipped with 15 stake pockets per side, total 30 stake pockets) | 10/66-10/68 | | NRHS |
| 10 | ZTTX | Trailer Train Co. | Apr-70 | | NRHS |
| 11 | ZTTX | Trailer Train Co. (flat cars equipped with 30 stake pockets, 15 per side; for transporting long poles) | 1/75-1/80; eliminated 1/92 | | NRHS |
| 12 | ZTTX | TTX Co. (flat cars equipped with 30 stake pockets, 15 per side; for transporting long poles) | added 1/92; 1/94-7/2000 | | NRHS |
| 13 | ZTTX | TTX COMPANY (TRAILER TRAIN COMPANY) | | | PWRC |
| 14 | ZTTX | Trailer Train (TTX Corporation) | | | RSRV |
| 15 | ZTTX | TTX COMPANY | | | SCAC4 |
