Advice for use-Every three months, the bristles of the toothbrush wear out, it's time to change only the head! Unclip the current head, clip the new one:) - Each head is composed of an ABS (Acrylonitrile Butadiene Styrene) base, a thermoplastic that is ultra-resistant to shock and humidity, a metal ring and bristles. These bristles are made of nylon for soft and medium heads, or polybutylene terephthalate (PBT) for extra-soft heads. Both nylon and PBT allow our toothbrush bristles to regain their shape after brushing. Everything is made in France.