Perifit Pump | Complete Breast Pump Replacement Parts Kit

1. What do we measure?

The nipple only, not the areola.

2. How do we measure it?

Using a ruler or tape measure, measure the nipple diameter at its base (top to bottom) in millimeters (mm).

3. How to choose the size?

Based on your measurement, select the corresponding flange size.

Example: if your nipple measures 16 mm in diameter, the recommended flange is size 21.

If you need a smaller size, you can order these Amazon adapters and combine them with our size 24 flanges.

💡 As a general rule, go with the larger size if you're between two sizes.

Simple rule: a comfortable pumping session = an effective one. Milk should flow easily, without pain or friction.

4. How do I know if I have the right flange size?

As soon as you receive the product, we recommend checking the flange size before starting to pump.

✅ Right size

The nipple is centered and moves freely; it doesn't touch the sides of the flange.

→ This is the right size.

❌ Too small

The nipple rubs against the side of the flange.

→ Try a larger flange.

❌ Too big

The nipple and excess areola tissue get pulled into the tunnel.

→ Try a smaller flange.

Other warning signs of an incorrect size:

• Visible redness;
• Nipple or areola turning white;
• Feeling that milk wasn't fully expressed.

If you notice any of these signs, try a different size. You can also reach out for guidance at support@perifit.co.

5. Did you know?

• Each breast may need a different size. In that case, two options:
  1. Buy two single Perifit Pumps in different sizes using code MIXMATCHDOUBLE.
  2. Buy a Perifit Pump Double and add an extra flange separately.
• Size depends on breast tissue and skin elasticity.
• Your size may change over the course of breastfeeding.
• The pump should be held securely in your bra, without compressing the breast, so milk can flow freely.
• For optimal support, use it with the Perifit nursing bra.

6. Practical info

• Most common sizes: 21 mm and 24 mm.
• All sizes are available individually on our site.

7. Choosing your nursing bra size