Bolt-On · fretless
fretless. spalted maple top, thin U-shaped 5-piece maple/jatoba neck, 24 clearly marked fret indicators, passive ESP Designed SB-4 pickups, active ABQ-3 EQ
| Construction | Bolt-On |
| Body | Ash |
| Neck | 5Pc Maple/Jatoba |
| Fingerboard | Rosewood |
| Neck Pickup | ESP SB-4N |
| Bridge Pickup | ESP SB-4B |
| Controls | Volume/Balance/ABQ-3 3-Band Active EQ |
| Bridge | LTD BB-604 w/ String Thru |
Artists documented playing the ESP B-204SM FRETLESS: Billy Sheehan, Steve DiGiorgio.