Features ： 1. Anti-tearing protective ring, more durable and prolong the usage. 2. Soft texture with thickened base, prevents vacuums while feeding. 3. Elasticity enhance stripes, more flexible and durable. 4. Textured finish prevents adhesion between the lips and the nipple. 5. Features a natural shape that feels more like a mother’s breast, to fit the baby’s mouth comfortably. 6. Enhanced fixing groove provides perfect closure to prevent leakage. 7. Extended venting valve, providing efficient air transmission. 8. Food-grade platinum silicone from Japan, nontoxic and incompliance with BS7368:1990. 9. Size indication on the bottom flange, easy to identify. 10. Breast-like texture, promotes healthy oral development. Material : Food grade platinum silicone(-40℃~+150℃) Instruction : gently supple the air vent before first use to avoid vacuums or stuffed milk flow, and sterilize it before every use.