1. Material: silicone 2. Spiral design to prevent choking due to excessive milk flow 3. Mimic the design of the areola bump, close to the natural effect of the mother areola 4. Cross-hole nipple with variable flow rate, baby can drink milk more smoothly 5. Petal shaped cups, fit different curves 6. Soft and elastic material, no deformation when stretching 7. Can be sterilized by high temperature, boiling or steam, which is more safe to use 8. Thin and lightweight, comfortable and comfortable, no burden on the breasts