Firm Bristle：Innovative Hollow Dual-Spiral Bristle Toothbrush-
Outer ring of spiral soft bristles conforms gently to tooth surfaces without irritating gums for mild protection; inner core of spiral firm bristles offers high tenacity and deformation resistance, specifically targeting stubborn interdental stains and heavy tartar buildup.
Combines durability and wear resistance with powerful cleaning action, ideally suited for individuals seeking a deep clean.