Neck Finishes Explained
Neck Finishes Explained
The neck finish is the top section of the bottle, around the opening, that holds the closure. Glass and closure must have matching finishes.
Reading a neck finish code
A neck finish description is made up of a few letters followed by two numbers.
DIN 18
The European industry standard for dropper bottles, based on the German norm. It sets the size, height and diameter of the neck.
GL18
The French version of the DIN neck finish, used for normed dropper bottles with a standardised height and diameter.
GPI / GCMI
The US norm, written as two numbers such as 22/400. Often used for cosmetic and para-pharma bottles with pumps or sprays.
PP28
PP stands for Pilfer Proof. It pairs with a tamper-evident closure that has a tear-off ring, which breaks when the cap is first opened.
What the numbers mean
The first number is the diameter in millimetres across the outside of the threads (and the inside of the cap). The second number is the thread style set by the Glass Packaging Institute: how many threads there are and how far they wrap around the neck.
| Code | Thread turns | Example |
|---|---|---|
| 400 | 1 turn | 45/400 on Saturn wide neck jars |
| 410 | 1.5 turns | 24/410 on Virgo bottles and larger Orion bottles |
| 415 | 2 turns | 18/415 on Virgo 30 ml bottles |
Match your glass to the right closure
DIN18 closures
Dropper caps, pipettes and roll-ons for Orion bottles.
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24/410 and 18/415 pumps
Lotion and treatment pumps for Virgo and Draco.
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PP28 caps
Tamper-evident caps and pourers for Aquarius.
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400-series lids
Classic and Modern lids for wide neck jars.
Shop now →Questions & answers
If bottles share a neck finish, will the same closure fit?
Usually, but not always. Pumps come with different dip-tube lengths, so check the compatible closures on each product page or ask our team.
Do other closures work with Miron® glass?
Most Miron glass uses industry-standard neck finishes. Ceres, Eris and Sirius jars and the Carina 500 ml vitamin jar have unique threads and need Miron closures. Test any third-party closure for fit and leaks first.
Test it with your product
Request a sample to see how Miron® glass works with your formulation before you order.
Flexible quantities
Sold in box quantities with a low minimum spend, plus volume pricing on trade orders.
UK stock, wider reach
Held in the UK for fast dispatch. International customers can ask about supply.
Not sure which closure you need?
Tell us which bottle or jar you're using and we'll help you find the right fit.