Barrel Power Supplies
| System | Voltage | Current | Barrel Size | Polarity |
|---|---|---|---|---|
| Group 1 – 9V DC, 5.5mm × 2.1mm, Centre Negative | ||||
| ZX Spectrum +2 / +2A / +3 | 9V DC | 2.1A | 5.5 × 2.1mm | 
|
| Super Nintendo (PAL) | 9V DC | 1.3A | 5.5 × 2.1mm |
|
| NES (PAL) | 9V DC | 1.3A | 5.5 × 2.1mm |
|
| Sega Saturn | 9V DC | 1.5A | 5.5 × 2.1mm |
|
| Sega Mega Drive / Genesis (Model 1) | 9V DC | 1.2A | 5.5 × 2.1mm |
|
| Sega Master System | 9V DC | 1.2A | 5.5 × 2.1mm |
|
| Group 2 – 9V DC, 3.5mm × 1.35mm, Centre Negative | ||||
| ZX Spectrum (16/48K) | 9V DC | 1.4A | 3.5 × 1.35mm |
|
| Atari 7800 | 9V DC | 1.0A | 3.5 × 1.35mm |
|
| Atari 2600 (VCS) | 9V DC | 0.5A | 3.5 × 1.35mm |
|
| Group 3 – 9V DC, 4.75mm × 1.7mm, Centre Negative | ||||
| Sega Game Gear | 9V DC | 1.2A | 4.75 × 1.7mm |
|
| Group 4 – 6V DC, 4.75mm × 1.7mm, Centre Negative | ||||
| Game Boy (DMG-01) | 6V DC | 0.7A | 4.75 × 1.7mm |
|
| Group 5 – 9–10V DC, 4.75mm × 1.7mm, Centre Positive | ||||
| Sega Mega Drive / Genesis (Model 2) | 10V DC | 0.85A | 4.75 × 1.7mm | 
|
| Atari Lynx (Model 1) | 9V DC | 1.0A | 4.75 × 1.7mm |
|
| Atari Lynx (Model 2) | 9V DC | 1.0A | 4.75 × 1.7mm |
|