Nylon material - Constructed of flexible nylon and Simple loop fits all types of floss for safe and comfortable use. Easy to Use - Flexible tip inserts into small spaces in a snapEasily threads floss under bridges, orthodontic appliances, implants and between connected crowns. Recommendation Use - Takes the difficulty out of cleaning around bridges, braces, and implants. Convenience Carry - Consists of 4 portable carrying case.The included case keeps threaders organized and clean. 100% satisfaction - We are committed to providing more reliable product and better customer service to our customers,If you have any questions or dissatisfaction with our products, please contact us in time and we will help you at any time.