Buy OXO Tot Sippy Cup Set - Green - The OXO Tot Sippy Cup Set grows with your child from age 6 months and up. The 7-ounce Sippy Cup with Handles is an ideal first Cup for babies transitioning from bottles. Its leak-proof valve prevents spills and releases pressure for comfortable sipping. Soft, non-slip Handles are angled so babies don't have to turn their wrists too far, and the Handles are removable for when baby's grasp develops. When baby is ready to transition from sippy to regular cup, remove the Sippy Cup lid and replace it with the OXO Tot Training Cup lid. The Training Cup lid has a transparent insert with perforations around the perimeter to control the flow of liquid when the child tilts the Cup to drink. A tipped Training Cup will also spill more gradually to minimize messes during the learning process. When ready, remove the perforated insert and the Training Cup converts to a regular Cup. All OXO Tot Sippy, Straw and Training Cup lids are interchangeable.