Durceler 18mm Silicone Flange Inserts – Convert 24/25mm Shields to 18mm (Medela, Spectra, Elvie, Freemie)

Overview

Durceler 18mm silicone flange inserts are designed to adapt standard 24mm–25mm breast shields to a narrower 18mm opening. Crafted from BPA-free silicone, these inserts are durable, clear, and gentle against the skin during pumping sessions. They slide inside your shield, creating a snug, comfortable tunnel that can feel more natural as you express milk.

Key benefits

• Broad compatibility with popular pumps and shields, including Medela, Spectra, Elvie, S18/S21/S23, Momcozy S9 Pro/S12 Pro, TSRETE, Bellababy, NCVI and Freemie 25mm cups.
• May improve tunnel fit and comfort for small-nippled users when pairing with larger shields.
• BPA-free silicone offers durability and a clear, skin-friendly surface for repeated use.
• Designed to work with most handsfree bra cups when placed inside 24/25mm shields. A gentle squeeze helps the insert seat fully.

How it works

The inserts reduce the nipple tunnel from 24–25mm to a more compact 18mm, enabling a more focused fit. To check compatibility, measure nipple diameter after a pumping session—16–17mm is a useful reference, or estimate the base circumference around 43.96–47.10mm before pumping.

Usage and care

• Insert inside the shield with a light squeeze to ensure an even seating.
• Rinse with mild soap after pumping and air-dry completely to preserve silicone clarity.
• Pair with your preferred handsfree bra for a streamlined pumping setup.

What’s included

• 2 Durceler 18mm silicone flange inserts per pack.

Notes on compatibility

These inserts are compatible with a broad range of 24–25mm shields and can adapt to multiple pump brands. While not a guarantee for every model, they are designed to offer a flexible, user-driven fit for many setups.