This brush was designed by a dentist to be easy to use and bite resistant. One size fits most human fingers and it can be molded to fit larger fingers. The 360 degree bristles help make brushing quicker and easier, because no matter how the finger brush is used you have the bristles to help break down the tartar and promote healthy teeth and gums in your best friend. One size fits all dogs. Constructed from BPA-free thermoplastic elastomers with non-toxic dye. Made in the USA.