BackTone 4000 - A biofeedback device for re-training postural habits. Worn for short periods daily, BackTone beeps whenever the wearer slouches. Straightening up turns the beep off. Users wear their BackTone during everyday simple tasks. Each time they slouch BackTone beeps, and continues to beep until they correct their posture. BackTone re-trains postural habits and allows you to extend your treatment regime even further.
| Waist (cm) | Size |
| Up to 88cm | Small |
| 88 - 102cm | Medium |
| 102 - 132cm | Large |