Material：High quality silicone<br>Size: <br>Size 4 Diameter:15.3<br>Size 5 Diameter:15.7<br>Size 6 Diameter:16.5<br>Size 7 Diameter:17.3<br>Size 8 Diameter:18.1<br><br>Feature:<br>1. Top grade，hypoallergenic，comfortable，flexible silicone - this silicone w