Inside each Bola, there is a small xylophone around which a ball moves. The xylophone emits positive waves through a gentle and melodic sound that soothes the baby during pregnancy and relaxes it after birth. The Bola comes with a waxed cord for tying. The neck is free of nickel and lead! It is suitable for all occasions, both formal and informal, including parties and baby showers. Thanks to the elegant packaging, it also makes an excellent gift idea. This model can be paired with a separately available chain.