BPA-free: All materials of Piifur sippy cups are BPA free. The cup body and the lid are made of PP, the straw is made of food grade silicone, and the gravity ball is made of PP and stainless steel. Anti-colic: There are air holes on the top of the cup lid, which can keep the air pressure inside and outside the cup balanced when the baby is drinking water, preventing stomach colic. 360° Drink: Piifur straw cup is equipped with a gravity ball, baby can drink water smoothly no matter what angle the baby flips the cup. Spill Proof: Smile-type valve straw can automatically open and close according to the baby's sucking, effectively preventing water from overflowing. Even upside down, the smile-type valve straw can effectively prevent water leakage. Integrated Handle: Piifur Straw Cup adopt an integrated handle design, which not only makes it easier for babies to grasp, but also makes cleaning and installation more convenient. BPA-free: All materials of Piifur sippy cups are BPA free. The cup body and the lid are made of PP, the straw is made of food grade silicone, and the gravity ball is made of PP and stainless steel. Anti-colic: There are air holes on the top of the cup lid, which can keep the air pressure inside and outside the cup balanced when the baby is drinking water, preventing stomach colic. 360° Drink: Piifur straw cup is equipped with a gravity ball, baby can drink water smoothly no matter what angle the baby flips the cup. Spill proof: Smile-type valve straw can automatically open and close according to the baby's sucking, effectively preventing water from overflowing. Leak proof: Even upside down, the smile-type valve straw can effectively prevent water leakage. Easy to Clean: The water cup is easy to disassemble and can be washed by hand or in the dishwasher. It is recommended to sterilize the cup by boiling it in a pot or using a steamer after each use.