The 3 a.m. questions
The ones that arrive in the middle of a feed, when there is nobody awake to ask. Sorted by where you are on the road, so you can skip what you already know.
Before the first session
How do I know which insert size to use?
Measure the nipple (not the areola) with the ruler before pumping, then add about 2–4mm. A 16mm nipple usually does well in a 19mm insert. Our flange size guide walks through it step by step, and the size finder on this page does the arithmetic.
Before the first session
Should I measure before or after pumping?
Before, when the nipple is at its resting size. Measuring again afterwards shows how much it swells, which helps if you are between two sizes.
Before the first session
Which pumps do Nursi Luna flange inserts fit?
They are made for 24mm shields and fit most 24mm shields for electric, wearable and manual pumps. Mothers tell us they use them in Medela, Spectra, BabyBuddha and Momcozy shields. They are not designed for 27–28mm shields.
The first weeks
Can each side use a different size?
Yes, and many mothers need exactly that. Every insert kit holds two of each size, so the left and right can wear different inserts.
The first weeks
What if I am between two sizes?
Start with the larger one for a few sessions. If the areola is being drawn into the tunnel, step down. Comfort is always the tiebreaker.
The first weeks
Does the wearable pump come with inserts?
Yes: 15, 17, 19 and 21mm inserts are in the box, together with milk storage bags.
Month two and beyond
How often should inserts be replaced?
Silicone softens and stretches with daily use. We recommend a fresh pair roughly every one to two months, or sooner if the seal feels weaker.
Month two and beyond
How do I clean the inserts?
Wash them with warm soapy water and the sponge brush in the kit, run them on the top rack of the dishwasher, or boil them with the rest of your pump parts.
Month two and beyond
Can inserts go in a steam steriliser?
Yes. They are food-grade silicone and handle boiling water, steam sterilisers and microwave steam bags.
When the pump feels weaker
Are the Spectra parts original Spectra parts?
No. They are made by Nursi Luna to fit Spectra S1, S2 and 9 Plus pumps. They are food-grade, BPA-free silicone and the tubing is longer than the original.
When the pump feels weaker
How often should valves and membranes be changed?
Valves every one to three months, membranes and backflow protectors every two to three — sooner if you pump several times a day. See our replacement guide.
Orders & prices
Where do I track or return an order?
In your account at the store where you ordered. Delivery, returns and warranty all run through that store.
Orders & prices
Why did the price change?
Prices are set by the store and move from day to day. The price at checkout is the one that counts.
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