{
  "schema_version": "compare-page.v2",
  "page_id": "available-breast-shield-sizes-by-product",
  "url": "https://robotrunk.com/compare/want/available-breast-shield-sizes-by-product",
  "title": "Available breast shield sizes by product",
  "question": "Which breast shield sizes are available, and how should a shopper choose one based on nipple size?",
  "answer": "Choosing a size: The supplied shield is 24 mm; nipple diameter should be measured and the selected shield should be slightly larger than the nipple.\n\nMEDELA PersonalFit Flex™ Breast Shields: Sizes range from S 21 mm through XXL 36 mm.\nMedela Harmony® Breast Pump with PersonalFit Flex™: PersonalFit Flex shields in 21, 24, 27 and 30 mm are listed as separately sold accessories.\nMedela Personal Fit Flex Breast Shield: The quoted variant is 24 mm.\nMedela Personal Fit Flex Breast Shields: The quoted variant is 27 mm.\nMedela PersonalFit Breast Shields: The shields are 36 mm.\nMEDELA Pump In Style Advanced Double Pumping Kit: The included breast shields are 24 mm.",
  "kind": "breastfeeding",
  "market": "US",
  "generated_at": "2026-10-09T18:20:08.541Z",
  "columns": [
    "Sizes",
    "Fit",
    "Compatibility"
  ],
  "notices": {
    "facts": "Every value in the table is a fact RoboTrunk checked, linked to the page it came from. A dash means no checked fact fills that cell.",
    "price": "Prices and stock change, so this page prints neither: each product name links to its RoboTrunk page, which shows them live."
  },
  "cited_facts": [
    {
      "ref": "p1.f1",
      "product": "MEDELA PersonalFit Flex™ Breast Shields",
      "field": "Sizes",
      "value": "Sizes range from S 21 mm through XXL 36 mm.",
      "stated_as": "S - 21mm — M - 24mm — L - 27mm — XL - 30mm — XXL - 36 mm",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p1.f2",
      "product": "MEDELA PersonalFit Flex™ Breast Shields",
      "field": "Fit",
      "value": "The shields adjust to the user's shape.",
      "stated_as": "the PersonalFit Flex™ shields adjust to your unique shape",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p2.f1",
      "product": "Medela Personal Fit Flex Breast Shields",
      "field": "Sizes",
      "value": "The quoted variant is 27 mm.",
      "stated_as": "Variant: 27 MM",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p3.f1",
      "product": "Medela Personal Fit Flex Breast Shield",
      "field": "Sizes",
      "value": "The quoted variant is 24 mm.",
      "stated_as": "Variant: 24 mm",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p3.f2",
      "product": "Medela Personal Fit Flex Breast Shield",
      "field": "Adjustment",
      "value": "Its flexible oval form rotates 360 degrees and adapts to the body.",
      "stated_as": "its flexible oval shape can be rotated 360 degrees and adapts to your body",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p3.f3",
      "product": "Medela Personal Fit Flex Breast Shield",
      "field": "Compatibility",
      "value": "The store says these breast shells work with all Medela breast pumps.",
      "stated_as": "These breast shells are compatible with all Medela breast pumps.",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p4.f1",
      "product": "Medela PersonalFit Breast Shields",
      "field": "Size",
      "value": "The shields are 36 mm.",
      "stated_as": "Medela PersonalFit Breast Shields 36 mm",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p4.f2",
      "product": "Medela PersonalFit Breast Shields",
      "field": "Compatibility",
      "value": "The store says they are compatible with all Medela breast pumps.",
      "stated_as": "compatible with all Medela breast pumps",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p5.f1",
      "product": "MEDELA Pump In Style Advanced Double Pumping Kit",
      "field": "Compatibility",
      "value": "The kit is for the Medela Pump In Style Advanced double electric breast pump.",
      "stated_as": "use the Medela Pump In Style® Advanced double electric breast pump",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p5.f4",
      "product": "MEDELA Pump In Style Advanced Double Pumping Kit",
      "field": "Shield size",
      "value": "The included breast shields are 24 mm.",
      "stated_as": "24 mm PersonalFit™ breast shields",
      "source_type": "listing",
      "source_url": "https://anb-baby.myshopify.com/products.json",
      "source_read_at": "2026-09-23T19:03:51.372Z"
    },
    {
      "ref": "p7.f4",
      "product": "Medela Harmony® Breast Pump with PersonalFit Flex™",
      "field": "Compatible shield sizes",
      "value": "PersonalFit Flex shields in 21, 24, 27 and 30 mm are listed as separately sold accessories.",
      "stated_as": "PersonalFit Flex breast shield sizes S (21 mm), M (24 mm), L (27 mm), XL (30 mm)",
      "source_type": "manual",
      "source_url": "https://www.medela.com/010-products/010-pumps/030-manual/010-harmony---manual-breast-pump/pdf-downloads/101041805-2021-05-b-harmony_flex_ifu_en_es_pt_ar_he-low.pdf",
      "source_read_at": "2026-09-25T10:30:33.111Z"
    },
    {
      "ref": "p7.f8",
      "product": "Medela Harmony® Breast Pump with PersonalFit Flex™",
      "field": "Shield fit",
      "value": "The supplied shield is 24 mm; nipple diameter should be measured and the selected shield should be slightly larger than the nipple.",
      "stated_as": "For proper sizing, measure the diameter of your nipple ( ¢7-01).\n2. Select the breast shield that is slightly larger than your nipple",
      "source_type": "manual",
      "source_url": "https://www.medela.com/040-services/manual-instructions/manual-breast-pump-manuals-instructions/harmony-breast-pump.pdf",
      "source_read_at": "2026-09-25T10:30:13.188Z"
    }
  ],
  "rows": [
    {
      "rank": 1,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/4007253540950",
      "name": "MEDELA PersonalFit Flex™ Breast Shields",
      "url": "/products/ucp/anbbaby-com/4007253540950",
      "why": "Sizes range from S 21 mm through XXL 36 mm.",
      "cells": [
        {
          "column": "Sizes",
          "fact": {
            "field": "Sizes",
            "value": "Sizes range from S 21 mm through XXL 36 mm.",
            "stated_as": "S - 21mm — M - 24mm — L - 27mm — XL - 30mm — XXL - 36 mm",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        },
        {
          "column": "Fit",
          "fact": {
            "field": "Fit",
            "value": "The shields adjust to the user's shape.",
            "stated_as": "the PersonalFit Flex™ shields adjust to your unique shape",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        },
        {
          "column": "Compatibility",
          "fact": null
        }
      ]
    },
    {
      "rank": 2,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/6560312754262",
      "name": "Medela Harmony® Breast Pump with PersonalFit Flex™",
      "url": "/products/ucp/anbbaby-com/6560312754262",
      "why": "PersonalFit Flex shields in 21, 24, 27 and 30 mm are listed as separately sold accessories.",
      "cells": [
        {
          "column": "Sizes",
          "fact": {
            "field": "Compatible shield sizes",
            "value": "PersonalFit Flex shields in 21, 24, 27 and 30 mm are listed as separately sold accessories.",
            "stated_as": "PersonalFit Flex breast shield sizes S (21 mm), M (24 mm), L (27 mm), XL (30 mm)",
            "source_type": "manual",
            "source_url": "https://www.medela.com/010-products/010-pumps/030-manual/010-harmony---manual-breast-pump/pdf-downloads/101041805-2021-05-b-harmony_flex_ifu_en_es_pt_ar_he-low.pdf",
            "source_read_at": "2026-09-25T10:30:33.111Z"
          }
        },
        {
          "column": "Fit",
          "fact": {
            "field": "Shield fit",
            "value": "The supplied shield is 24 mm; nipple diameter should be measured and the selected shield should be slightly larger than the nipple.",
            "stated_as": "For proper sizing, measure the diameter of your nipple ( ¢7-01).\n2. Select the breast shield that is slightly larger than your nipple",
            "source_type": "manual",
            "source_url": "https://www.medela.com/040-services/manual-instructions/manual-breast-pump-manuals-instructions/harmony-breast-pump.pdf",
            "source_read_at": "2026-09-25T10:30:13.188Z"
          }
        },
        {
          "column": "Compatibility",
          "fact": null
        }
      ]
    },
    {
      "rank": 3,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/4007253508182",
      "name": "Medela Personal Fit Flex Breast Shield",
      "url": "/products/ucp/anbbaby-com/4007253508182",
      "why": "The quoted variant is 24 mm.",
      "cells": [
        {
          "column": "Sizes",
          "fact": {
            "field": "Sizes",
            "value": "The quoted variant is 24 mm.",
            "stated_as": "Variant: 24 mm",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        },
        {
          "column": "Fit",
          "fact": {
            "field": "Adjustment",
            "value": "Its flexible oval form rotates 360 degrees and adapts to the body.",
            "stated_as": "its flexible oval shape can be rotated 360 degrees and adapts to your body",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        },
        {
          "column": "Compatibility",
          "fact": {
            "field": "Compatibility",
            "value": "The store says these breast shells work with all Medela breast pumps.",
            "stated_as": "These breast shells are compatible with all Medela breast pumps.",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        }
      ]
    },
    {
      "rank": 4,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/4007253573718",
      "name": "Medela Personal Fit Flex Breast Shields",
      "url": "/products/ucp/anbbaby-com/4007253573718",
      "why": "The quoted variant is 27 mm.",
      "cells": [
        {
          "column": "Sizes",
          "fact": {
            "field": "Sizes",
            "value": "The quoted variant is 27 mm.",
            "stated_as": "Variant: 27 MM",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        },
        {
          "column": "Fit",
          "fact": null
        },
        {
          "column": "Compatibility",
          "fact": null
        }
      ]
    },
    {
      "rank": 5,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/1706915299428",
      "name": "Medela PersonalFit Breast Shields",
      "url": "/products/ucp/anbbaby-com/1706915299428",
      "why": "The shields are 36 mm.",
      "cells": [
        {
          "column": "Sizes",
          "fact": {
            "field": "Size",
            "value": "The shields are 36 mm.",
            "stated_as": "Medela PersonalFit Breast Shields 36 mm",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        },
        {
          "column": "Fit",
          "fact": null
        },
        {
          "column": "Compatibility",
          "fact": {
            "field": "Compatibility",
            "value": "The store says they are compatible with all Medela breast pumps.",
            "stated_as": "compatible with all Medela breast pumps",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        }
      ]
    },
    {
      "rank": 6,
      "merchant": {
        "slug": "anbbaby-com",
        "display_name": "anbbaby.com"
      },
      "product_id": "gid://shopify/Product/1706916675684",
      "name": "MEDELA Pump In Style Advanced Double Pumping Kit",
      "url": "/products/ucp/anbbaby-com/1706916675684",
      "why": "The included breast shields are 24 mm.",
      "cells": [
        {
          "column": "Sizes",
          "fact": {
            "field": "Shield size",
            "value": "The included breast shields are 24 mm.",
            "stated_as": "24 mm PersonalFit™ breast shields",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        },
        {
          "column": "Fit",
          "fact": null
        },
        {
          "column": "Compatibility",
          "fact": {
            "field": "Compatibility",
            "value": "The kit is for the Medela Pump In Style Advanced double electric breast pump.",
            "stated_as": "use the Medela Pump In Style® Advanced double electric breast pump",
            "source_type": "listing",
            "source_url": "https://anb-baby.myshopify.com/products.json",
            "source_read_at": "2026-09-23T19:03:51.372Z"
          }
        }
      ]
    }
  ]
}