How to Use Dr. Brown's Silicone Rings with a Chiller
By Dr. Brown's - Happy feeding™ | Published: 2026-10-19
Category: How-to Guides
Learn how to correctly install Dr. Brown's Silicone Rings on your breast milk or formula chiller to prevent leaks and keep milk fresh on the go.
Quick answer
Install the large outer silicone ring around the chiller lid and the small inner ring around the center post to create a leak-proof seal.
Why silicone rings matter for your chiller
The silicone rings are the only barrier between the chiller and the bottle opening. If they are missing, worn, or incorrectly seated, the chiller will not seal properly and milk or formula can leak into the bottle cap or out of the bottle entirely.
Dr. Brown's Silicone Rings for Breast Milk & Formula Chiller come in two sizes: a large outer ring (9.5 cm/3.74 in diameter) and a small inner ring (5.3 cm/2.08 in diameter). Each has a specific position. Mixing them up or skipping one will break the seal.
When to replace the rings
Inspect the rings before every use. Replace them if you see cracks, tears, or permanent flattening. A ring that has lost its shape will not hold the chiller tightly against the bottle rim. Dr. Brown's sells a two-pack of replacement rings so you always have a spare set on hand.
How to install the silicone rings on your chiller
- Step 1: Identify the rings: Hold the two rings side by side. The large ring (9.5 cm diameter) goes on the outer edge of the chiller lid. The small ring (5.3 cm diameter) goes around the center post. Mixing the rings is the most common mistake. If the small ring is forced onto the outer edge, it will not seal and the chiller will leak.
- Step 2: Install the large outer ring: Stretch the large ring over the rim of the chiller lid and seat it evenly in the groove. Run your finger around the entire ring to confirm it is fully seated with no twists. A twisted outer ring creates a gap that lets air and liquid pass through. Check that the ring lies flat before moving to the next step.
- Step 3: Install the small inner ring: Place the small ring around the center post of the chiller lid and press it down into the inner groove. Make sure it sits flush against the post and does not ride up. If the inner ring is not pressed all the way down, the chiller may not seal against the bottle nipple or cap.
- Step 4: Test the seal: Fill the chiller with breast milk or formula, attach it to a bottle, and turn the bottle upside down over a sink. A few drops of liquid indicate a poor seal. Remove the chiller, recheck both rings, and repeat the test. Always test with water or milk before leaving the house. A leak discovered at home is a quick fix; a leak discovered in a diaper bag is a mess.
Product details
- Dr. Brown's Silicone Rings for Breast Milk & Formula Chiller – 2 Pieces: Replacement Silicone Rings for the Dr. Brown’s Breast Milk & Formula Chiller. Includes: 1 large outer silicone ring (9.5 cm/3.74 in diameter), 1 small inner silicone ring (5.3 cm/2.08 in diameter). Having a spare set means you can replace a worn ring immediately instead of using a chiller that may leak.
Dr. Brown's Silicone Rings for Breast Milk & Formula Chiller – 2 Pieces
