The First Years Spill-Proof Gripper Sipper cups are a hit with moms and kids! Moms love the easy-to-clean One Piece Lid, which features a spill-proof valve system that is built into the lid! The First Years spill-proof One Piece Lid has no small parts to lose at daycare or down the garbage disposal! The cup is designed to be easy for children to hold with a no slip grip! Dishwasher safe and BPA free.