Key Features & DesignSpoutless 360° Rim: Enables toddlers to drink comfortably from any side of the rim just like an adult glass, promoting proper muscle alignment and natural oral development.Spill-Proof Valve: An internal silicone pressure-activated valve opens exclusively when the toddler's lip applies subtle pressure while sipping. The vessel automatically seals shut the moment drinking stops, making it safely inverted-watertight.