Dr. Brown's Natural Flow Narrow Baby Bottle Silicone Nipple, Level 4, 2-Pack | live price, prepared checkout

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Checked facts

Each fact below was checked against the source it cites before it was published. Each carries that source's link and the time RoboTrunk read it. 25 checked facts, checked 2026-10-11T19:07:25.688Z. Research depth: trimmed read. Deep read: the store's own data and 7 outside pages (the store's own product page; maker page; manual; spec sheet; review; regulator recall search (CPSC (United States)); regulator recall search (Health Canada)), each read in full by RoboTrunk and trimmed to its main content, then written up and checked. Facts from the maker or a manual quote the page word for word; what real users report is summarised with a link to the page read. Recall status was checked directly with CPSC (United States), Health Canada: The CPSC recall search for this manufacturer returned an error and no valid record, and the only Health Canada recall naming Dr. Brown's covers Lovey Pacifier & Teether Holders, a different product, not this nipple. No recall applying to this exact model was found.

• compatibility: The nipple fits all of Dr. Brown's narrow bottles.. Source: https://4f71f1-4.myshopify.com/products.json (listing), read 2026-10-11T07:16:33.630Z.
• material and feel: The nipple is made of super-soft 100% silicone.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.
• colic claim: Dr. Brown's repeats that the silicone nipple with the anti-colic internal vent system is clinically proven to reduce colic.. Source: https://drbrownsbaby.com/pages/instructions (manual), read 2026-10-11T18:42:31.780Z.
• compatibility: All levels of Dr. Brown's narrow silicone nipples can be used with the original Natural Flow, Zero-Resistance Options+ and Zero-Resistance Specialty Feeding System bottles.. Source: https://www.drbrownsmedical.com/wp-content/uploads/2022/03/Dr.-Browns-Medical-Nipple-Selection-Guide-for-all-Zero-Resistance%E2%84%A2-Bottle-Systems-English.pdf (manual), read 2026-10-11T18:42:34.941Z.
• flow behaviour: One buyer describes the Level 4 narrow teat's flow as a steady but gentle drip that allowed their baby time to swallow rather than being flooded.. Source: https://www.drbrowns.co.uk/collections/options-teats/products/dr-browns-narrow-neck-options-level-4-teats (review), read 2026-10-11T18:42:36.578Z.
• flow levels: The store listing says there are six nipple flow levels, from 0m+ through 9m+ to thicker liquids; the Medical selection guide says eight levels, so the sources disagree on the count.. Source: https://4f71f1-4.myshopify.com/products.json (listing), read 2026-10-11T07:16:33.630Z.
• colic claim: With the anti-colic internal vent system the nipple is stated to be clinically proven to reduce colic.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.
• number of levels: The Medical selection guide says Dr. Brown's designed eight nipple levels and flow rates; the store listing says six, so the sources disagree on the count.. Source: https://www.drbrownsmedical.com/wp-content/uploads/2022/03/Dr.-Browns-Medical-Nipple-Selection-Guide-for-all-Zero-Resistance%E2%84%A2-Bottle-Systems-English.pdf (manual), read 2026-10-11T18:42:34.941Z.
• cleft palate feeding: One buyer moved to the Level 4 narrow teat from latex vented teats used for cleft palate feeding and reported it suited that use.. Source: https://www.drbrowns.co.uk/collections/options-teats/products/dr-browns-narrow-neck-options-level-4-teats (review), read 2026-10-11T18:42:36.578Z.
• age range: The suggested age range is only a guide and a baby's preferred flow rate may differ from it.. Source: https://4f71f1-4.myshopify.com/products.json (listing), read 2026-10-11T07:16:33.630Z.
• feeding benefits: The maker says the nipple and bottle provide a more comfortable feeding experience by decreasing spit-up, burping and gas.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.
• Level 4 selection: Level 4 is recommended for an infant with advanced feeding skills.. Source: https://www.drbrownsmedical.com/wp-content/uploads/2022/03/Dr.-Browns-Medical-Nipple-Selection-Guide-for-all-Zero-Resistance%E2%84%A2-Bottle-Systems-English.pdf (manual), read 2026-10-11T18:42:34.941Z.
• mess and comfort: The same feedback says feeding became much drier and more pleasant, and the buyer would recommend the teat for that purpose.. Source: https://www.drbrowns.co.uk/collections/options-teats/products/dr-browns-narrow-neck-options-level-4-teats (review), read 2026-10-11T18:42:36.578Z.
• care and cleaning: The nipple is safe in the dishwasher on the top rack only, in electric and microwave sterilizers, or in boiling water.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.
• Level 4 selection: Level 4 may suit an infant transitioning to finger foods and cup drinking.. Source: https://www.drbrownsmedical.com/wp-content/uploads/2022/03/Dr.-Browns-Medical-Nipple-Selection-Guide-for-all-Zero-Resistance%E2%84%A2-Bottle-Systems-English.pdf (manual), read 2026-10-11T18:42:34.941Z.
• impatient baby: A buyer with an impatient nine-month-old found the faster flow a good upgrade.. Source: https://www.drbrowns.co.uk/collections/options-teats/products/dr-browns-narrow-neck-options-level-4-teats (review), read 2026-10-11T18:42:36.578Z.
• materials safety: The nipple is BPA free.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.
• thicker liquids: For infants using the Specialty Feeding System, the guide says medical professionals reported Levels 2, 3 and 4 efficiently dispense thicker liquids; Dr. Brown's Medical does not endorse thickening oral feedings.. Source: https://www.drbrownsmedical.com/wp-content/uploads/2022/03/Dr.-Browns-Medical-Nipple-Selection-Guide-for-all-Zero-Resistance%E2%84%A2-Bottle-Systems-English.pdf (manual), read 2026-10-11T18:42:34.941Z.
• real-world age: Feedback on the page includes a six-month-old using this teat even though it is labelled 9m+, so some families start it earlier than the suggested age.. Source: https://www.drbrowns.co.uk/collections/options-teats/products/dr-browns-narrow-neck-options-level-4-teats (review), read 2026-10-11T18:42:36.578Z.
• Level 4 flow: Level 4 is a fast flow nipple designed for babies who are more developed or prefer a quick flow.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.
• flow rate testing: The stated nipple flow rates are based on testing with thin liquid viscosity.. Source: https://www.drbrownsmedical.com/wp-content/uploads/2022/03/Dr.-Browns-Medical-Nipple-Selection-Guide-for-all-Zero-Resistance%E2%84%A2-Bottle-Systems-English.pdf (manual), read 2026-10-11T18:42:34.941Z.
• review volume: Only three reviews are shown on the page and all are positive, so the amount of user feedback is limited.. Source: https://www.drbrowns.co.uk/collections/options-teats/products/dr-browns-narrow-neck-options-level-4-teats (review), read 2026-10-11T18:42:36.578Z.
• flow consistency: Flow rates are engineered not to change between nipples of the same level, so a level gives a consistent flow.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.
• signs flow is too fast: Signs that a nipple flow is too fast for an infant include falling asleep at the start of feeds, gulping, hard swallowing, coughing, choking, taking a long time to eat small amounts, fluid loss from the mouth and bottle refusal.. Source: https://www.drbrownsmedical.com/wp-content/uploads/2022/03/Dr.-Browns-Medical-Nipple-Selection-Guide-for-all-Zero-Resistance%E2%84%A2-Bottle-Systems-English.pdf (manual), read 2026-10-11T18:42:34.941Z.
• latch: The breast-like nipple shape is said to encourage a proper latch and ease the transition between breast and bottle.. Source: https://drbrownsbaby.com/products/drbrowns-natural-flow-level-4-narrow-baby-bottle-silicone-nipple-fast-flow-9mplus-100percent-silicone-bottle-nipple-2-pack (guide), read 2026-10-11T18:42:19.239Z.

The full evidence pack, with every citation, source and gap.

Questions we researched but could not confirm

Every fact above is cited. To find them we read the store listing, the maker's page, the manual, the spec sheet, owner reviews and the recall records of CPSC (United States) and Health Canada and searched for regulator recall notices, blogs, owner forums and video reviews. We also chased the questions below across those sources and found no reliable answer, so you know exactly where the evidence ends and never have to guess.

• What are the exact diameter and height of this nipple?
• How often should these silicone nipples be replaced?
• Will the nipple fit narrow bottles from other brands, such as Philips Avent?
• What is the total weight of the two-nipple pack?
• Is the nipple latex-free as well as BPA-free?
• Does the pack include the collar and cap or only the nipples?
• What warranty does Dr. Brown's offer on this nipple?
• What is the measured flow rate of the Level 4 nipple in millilitres per minute?
• Can the nipples be washed in a steam sterilizer basket with the collar attached?
• Are these nipples sold in packs larger than two?
• Do the nipples have a shelf life or expiry date?
• Is the nipple compatible with Dr. Brown's glass narrow bottles?

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