Nuby 2 Pack Feeding Nipples - ClearNuby Feeding nipples fits standard neck bottles (2 pack). Three flow - adjustable for slow, medium and fast flow rates. Anti-colic air system prevents ingestion of air by baby. Teething nubs massage and stimulate gums. Features include: •Three flow - adjustable for slow, medium and fast flow rates •Anti-colic air system prevents ingestion of air by baby •Teething nubs massage and stimulate gums