Dr. Brown's Wide-Neck Transition Sippy Spouts offers your little one the best and easiest transition from bottle to cup. Sippy Spouts are 100% Silicone and fits Dr. Brown's Options Wide-Neck 5oz and 9oz Bottles. Spill proof, easy to sip, and easy to clean. Remove vent and nipple to transition to sippy spout. Not intended for use with Dr. Brownâ€™s Original Wide-Neck Bottles, please use with Dr. Brownâ€™s Options Wide-Neck Bottles only. Made in China.