The Transition Value Pack is 4 Cups in 1, Taking Baby from Bottle Feeding to Toddler Training in One Great Value Pack. The Base Fits Each Lid. Simply Change Lids as Baby Grows, Catering to Every Age and Stage from 4 Months to 12 Months Plus. The Set Includes: Teat Lid (4 Month Plus) with A Fast Flow (Stage 3) Silicone Teat with Handles and a Cover; Spout Lid (4 Months Plus) with a Soft Silicone Spout That is Gentle On Baby Gums; Sippy Straw Cup Lid (6 Months Plus) with a Unique Weighted Straw; and a Training Lid (12 Months Plus) Teaches Kids How TO Drink From A Cup, Offering Easy Free Flow Drinking With a Unique Window Lid.