Sol-o features a powerful, rumbling vibrator inside its grooved, silicone wheel. The elongated silicone handle allows you to easily roll sol-o across the neck, back and body providing muscle relief to those hard-to-reach places. As the grooved surface stimulates the outer muscles the vibration awakens the nerves deeper in the body for powerful muscle relief. Features: Multispeed Vibrates Rechargeable Battery (Included)