Injector needle codes explained: how to read the series, diameter (D) and length (L)
An injector needle code is a short reference that says which needle line a part belongs to, how long the needle is and how wide its tube is. In the ZUST Needles system, FOM L305 D4 quadro reads as: the FOM line, 305 mm overall length (L), 4 mm outer tube diameter (D), four tubes in one head position.
A code only helps when it is read exactly. One misread figure can leave a plant with a needle of the right line and the wrong length.
How a ZUST Needles code is built
Every code on our brand pages follows the same order: the series prefix, the L number, the D value and, where it applies, a word that describes the configuration or the tip.
| Part | Example | What it tells you |
|---|---|---|
| Series prefix | FOM, SCH, INJS | The ZUST Needles line made for one machine brand. FOM needles are suitable for Fomaco injectors, SCH needles for Schroder injectors, INJS needles for Inject Star injectors. |
| L number | L305 | The overall length of the needle in millimeters. L352 is 352 mm, L205 is 205 mm. |
| D value | D4 | The outer diameter of the tube in millimeters. A comma is the decimal point, as in European writing: D2,5 is 2.5 mm. When the inner diameter matters, we state the outer diameter (OD) and the inner diameter (ID) separately. |
| Description word | quadro, hypodermic, three-edge tip | The configuration or the tip. Quadro means four tubes in one head position, hypodermic means a slender tip with an open front, three-edge means a triangular tip. |
We make all of these needles to our own designs and we are not an agent of Fomaco, Schroder, Inject Star or any other machine builder.
Worked examples from our product pages
Three codes from our product tables show three kinds: a complete one, one without a D value, and one with two figures in the D position.
FOM L305 D4 quadro. The FOM line, 305 mm overall length, 4 mm outer diameter, quadro configuration. The product table lists it as a quadro needle of 4 mm.
SCH L352 hypodermic. The SCH line, 352 mm overall length, hypodermic tip. The D value is missing because the table lists this code for all diameters: the L number fixes the length and you state the diameter you need.
FOM L205 D 2/1,6 quadro. The FOM line, 205 mm overall length, quadro configuration, and two figures in the D position. The first figure, 2, is the outer diameter of the tube. The second figure, 1.6, is the working diameter: the tube narrows to that size, and this keeps the needle sturdy while it injects delicate products. The product table lists it with 1.6 mm hypodermic tips for fish.
The full list of codes for each machine brand sits on the brand pages: FOM needles, SCH needles and INJS needles.
What a code does not tell you
The code gives the length, the outer diameter and the configuration or tip, but it does not tell you the following:
- The fitting. Each injector manufacturer uses their own type of needle fitting. It is very important information in order to offer a needle that will fit the machine, so we ask for the brand and model of the injector next to the code. The role of the needle inside the head is explained on injector-needles.com.
- The hole pattern. Many entries in our tables say “different hole patterns available”. How many holes, how large and where, is chosen for the brine, as described in how to match bore and hole pattern to brine.
- The wall thickness. D is the outer diameter, so the code does not give the inner one. Wall thickness sets the inner diameter, which affects how much brine the needle passes and how well it resists breaking.
- The origin of the number. Product codes shown on this website are ZUST Needles’ own product references unless expressly stated otherwise. They are not the part numbers of the machine builder.
How to quote a code in an inquiry
A complete inquiry is short and contains these items:
- The code exactly as it is written on our page, including spaces and commas.
- The injector brand and model, so we can confirm the fitting.
- The overall length of the needle you run today, in millimeters, and its outer diameter.
- The product you inject and the brine you use, so the hole pattern can be set.
When the code is unknown, a photograph of the needle and its mounting, the two measurements and the injector brand and model are enough to start. Our compatibility cross-reference guide shows how brand, series and code line up, and the glossary defines terms such as bore and wall thickness.
Key takeaways
- A ZUST Needles code reads in four steps: series prefix, L number, D value, description word.
- Two figures in the D position, as in D 2/1,6, mean a tapered needle: the first figure is the outer diameter and the second is the working diameter.
Frequently asked questions
What does the L mean in an injector needle code?
In our codes L is the overall length of the needle in millimeters. FOM L305 is 305 mm long, SCH L352 is 352 mm long. Quote the L number exactly as it appears on the product table.
What does the D mean in an injector needle code?
D is the outer diameter of the needle tube in millimeters. D4 is a 4 mm tube and D2,5 is a 2.5 mm tube, because we write the decimal point as a comma. When the inner diameter matters, we state the outer diameter (OD) and the inner diameter (ID) separately.
What does D 2/1,6 mean in an injector needle code?
D 2/1,6 is a tapered needle. The first figure, 2, is the outer diameter of the tube in millimeters, and the second figure, 1.6, is the working diameter. The slim working end suits delicate products such as fish.
Is a ZUST Needles code the same as a machine builder part number?
No. Our codes are not the part numbers of the machine builder. We design and manufacture every needle ourselves, and the prefix only shows which injector the needle is suitable for.
What do I send if I do not know the code of my needle?
Send the injector brand and model, a photograph of the needle and its mounting, the overall length in millimeters and the outer diameter. Add the product and the brine you run. From these we can identify the line, confirm the fitting and set the hole pattern.
When the code is missing or unclear
Our codes are grouped by machine brand on our products page. If yours is not there, or the marking has worn away, write through our contact page with whatever you can read and the injector model. Choosing a needle from scratch is covered in how to choose an injector needle.