| H-x mortor gunboat | H-x | |
| Ha-x submarine | Ha-x | |
| I-x submarine | I-x | |
| No.x | No.x | |
| No.x Destroyer | DD-x | |
| No.x Escort | CD-x | |
| No.x Escort boat | CDa-x | |
| No.x Landing ship | T-x | |
| No.x Minelayer (aux.) | Ma-x | |
| No.x Minesweeper | W-x | |
| No.x Minesweeper (aux.) | Wa-x | |
| No.x Mortor torpedo boat | MTB-x | |
| No.x Patrol boat | PB-x | |
| No.x Patrol boat (aux.) | PBa-x | |
| No.x Submarine | SS-x | |
| No.x Submarine chaser | CH-x | |
| No.x Submarine chaser (aux.) | CHa-x | |
| No.x Torpedo boat | TB-x | |
| Ro-x submarine | Ro-x |