Dr Brown's - Narrow-Neck "Options" Vent Replacement Kit Dr. Brown's Natural Flow Options Bottle Replacement Vent Kit replaces worn or lost parts. For use with Dr. Brown's Options 8 oz. bottle Features: - Features a patented internal vent system - Top-rack dishwasher safe - Dr. Brown's Natural Flow Options bottles help reduce colic, spit-up, burping, and gas (sold separately) - Made in USA What's Included: - 2 vent inserts - 2 vent reservoirs Specifications: - Weight: 500g - Dimensions: 22cm × 16.5cm × 21cm - Warranty: Based on Manufacturing Defects