Thanks to the material used in the mouthpiece and to the Willo Smart Sensor, Willo doesn't require a fully customized mouthpiece.
The size of the mouthpiece is still extremely important, however. To ensure the efficacy of Willo and to make sure that you will find the right fit, we will be proposing 5 different sizes of mouthpiece, XS, S (mostly for children and young adolescents), M, L and XL.
To know how to pick the right mouthpiece size for your kid, please follow this article How do I know my mouthpiece size?