Thread guide
Here's how to identify the thread of your aerator in just 4 steps. Depending on your tap, the Alb Filter Duo needs a matching adapter. This guide helps you determine the thread of your aerator and choose the right adapter.
The right adapter in 4 steps
Follow this short guide to reliably determine the thread of your aerator.
1Remove the aerator
Most taps have a jet regulator – also known as an aerator. Unscrew the jet regulator anticlockwise, by hand or with a tool (e.g. pliers with a cloth, or a coin). Important: it is the thread of the aerator that you need to determine, as this measurement decides which adapter fits.
2Determine the thread type
Male thread (external): the threads face outwards.
Female thread (internal): the threads are on the inside. Check whether the aerator has a male or female thread – this determines which table below applies.
3Measure the thread
Measure the diameter of the thread. This is most accurate with a calliper (high to very high accuracy); alternatively, use a ruler (medium accuracy). For male threads, measure at the outer edge of the threads; for female threads, at the inner edge. Alternatively, the dimension is often given in the tap's instructions.
Male thread (external)
ameasure with a calliper
Accuracy: high – very high
The thread is measured at the outer edge of the thread teeth. To do this, position the calliper as shown in the illustration below and read off the value.
Male thread (external)
bmeasure with a ruler
Accuracy: medium
Place the zero mark of the ruler at the outer edge of the thread teeth. Then read off the mm value on the opposite side of the thread.
NOTE: because the thread is on the outside, a male thread is easier to measure with a ruler than a female thread.
Female thread (internal)
cmeasure with a calliper
Accuracy: high – very high
Place the inside jaws of the calliper at the inner edge of the thread teeth. Then read off the mm value on the opposite side of the thread.
Female thread (internal)
dmeasure with a ruler
Accuracy: medium
Place the zero mark of the ruler at the inner edge of the thread teeth. Then read off the mm value on the opposite side of the thread.
Alternatively: user manual
eTap manual
If you have the user manual for the tap, you can often find the exact thread sizes there too.
4Compare with the table
Compare the measured diameter with the relevant table (male or female thread) and select the recommended adapter directly.
(See below)
Prefer a video?
The thread guide on video
In the video, Patrick explains when an adapter is needed, why there are different adapters and how to measure your thread correctly.
Male thread (external)
Does your aerator have a male thread? Find your measured diameter and add the matching adapter to your cart.
| Measured diameter | Adapter required | |
|---|---|---|
| 15.8 mm (M16 male) | M22 male → M16 male | Add to cart |
| 16.3 mm (M16.5 male)common on IKEA models | M22 male → M16.5 male | Add to cart |
| 17.8 mm (M18 male) | M22 male → M18 male | Add to cart |
| 18.3 mm (M18.5 male)common on IKEA models | M22 male → M18.5 male | Add to cart |
| 19.8 mm (M20 male) | M22 male → M20 male | Add to cart |
| 20.8 mm (M21 male) | M22 male → M21 male | Add to cart |
| 21.3 mm (M21.5 male)rare | M22 male → M21.5 male | Add to cart |
| 21.8 mm (M22 male) | M22 male → M22 male | Add to cart |
| 23.8 mm (M24 male)Included with the Duo | M22 male → M24 male | Add to cart |
| 27.8 mm (M28 male) | M22 male → M28 male | Add to cart |
Female thread (internal)
Does your aerator have a female thread? Find your measured diameter and add the matching adapter to your cart.
| Measured diameter | Adapter required | |
|---|---|---|
| 14.9 mm (M16 female) | M22 male → M16 female | Add to cart |
| 16.9 mm (M18 female) | M22 male → M18 female | Add to cart |
| 18.9 mm (M20 female) | M22 male → M20 female | Add to cart |
| 20.9 mm (M22 female)Standard | — | No adapter needed |
| 26.9 mm (M28 female) | M22 male → M28 female | Add to cart |
Coarse and fine threads (pipe threads)
Can't clearly identify your thread? Rare coarse threads (pipe threads) have a greater spacing between the threads. If none of the values above fits, it is usually one of these inch threads.
| Thread type | Adapter required | |
|---|---|---|
| 3/8 inch male thread≈ 16.7 mm | M22 male → 3/8 inch male | Add to cart |
| 1/2 inch male thread≈ 21.0 mm | M22 male → 1/2 inch male | Add to cart |
| 3/8 inch female thread≈ 15.3 mm | M22 male → 3/8 inch female | Add to cart |
How to install the Alb Filter Duo with an adapter
1Unscrew the aerator
Unscrew the existing jet regulator (aerator) from the tap anticlockwise.
2Screw on the adapter
Screw the matching adapter onto the thread of the tap. Make sure it forms a tight seal.
3Screw on the Alb Filter Duo
Fit the Alb Filter Duo onto the adapter and tighten it by hand. Done – filtered water is flowing.
Personal advice on your thread
Stuck? Write to us at info@schnarwiler.ch and ideally include: a photo of the aerator with the measuring tool held against it, a photo of the installation situation and a picture of the tap. Together we'll find the right adapter.
Free adapter exchange
We recommend checking thread compatibility before you buy. If the M24 adapter supplied doesn't fit, we'll be happy to exchange it for the right adapter. Just send us a message with your order number.