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Fitting Guide
Why is it important to measure?
Having the correct size breast shield or flange while pumping is crucial for both comfort and milk output. Using the incorrect flange size can also result in discomfort, pain or reduced output. Use our measuring guide to make sure you get the right size and you're make the most of your pumping sessions.
The nipple diameter is actually the most important part to get your pump fitting comfortably and correctly. Our standard size 24mm pumps fit a lot of Mums, but make sure to follow the guide before ordering your pump just in case you need to order a different size flange.
Our pumps are suitable for breasts of all sizes! Just make sure you're wearing a supportive bra to hold the pump firmly against your breasts, you've measured and your using the correct flange size, and the pump will work for you.
Find your correct size
Step 1
Measure before a pumping/ feeding session.
Stimulate your nipple to make it perk up. This will help replicate the size of your nipple when pumping.
Step 2
Using a ruler, measure your nipple from bottom to top to where your nipple meets the areola (see diagram provided).
Measure only the nipple, excluding the areola, which is the outer edge surrounding your nipple. Express the measurement in millimeters, where 1cm is equivalent to 10mm.
Step 3
Get the measurement of both nipples (yes the left and right can each be different!) and the size measurement is done.
What size do I need?
Find your correct size in the table. The flange needs to have the correct amount of room to allow for movement of the nipple within the tunnel whilst pumping - in the table above we've accounted for this in our recommendations.
The Night Owl pumps come either with either 24mm or 27mm shields.
For smaller sizes we have 13mm, 15mm, 17mm, 19mm or 21mm flange inserts available. To see how these work head over to our how to guide.
Please note the flange inserts are only compatible with the 24mm shields.
You can view our full range of accessories here!
How do I know if my flange size is correct?
Too small
During pumping if your nipples are rubbing against the sides of the tunnel, the fit may be too small. Pain, redness or reduced output can be a signs too. Use our measuring guide as you may need a larger size flange insert or shield!
Good fit
During pumping you nipples should move freely in and out of the tunnel. Their should be space around your nipple, but so much that too much of your areola is sucked into the tunnel.
Too big
If there is a large gap between your nipples and the tunnel or during pumping if you feel too much of your areola getting sucked in, the fit may be too big. Pain, redness or reduced output can be a signs too. Use our measuring guide as you may need a smaller size flange insert or shield!
Need more help? Head over the our contact us page and we'd be happy to answer any questions you ay have!