A brass rain head and a replaceable mineral cartridge. Water arrives warm, soft, and the colour of late afternoon.
Twelve years of development. One product. Nine finishes. Fitted by appointment.
We make a single object and we have no plans for a second. The AU-1 is finished, in the sense that there is nothing further we would like to do to it.
A 220 mm brass rain head with a replaceable cartridge seated behind the face plate. Mains water passes through the cartridge on its way out and leaves it a deep, even gold — not a tint on the surfaces it touches, but a colour carried in the water itself.
It does not stain. It will not mark grout, stone, enamel or hair. It rinses clear, completely, every time, and we have tested this for longer than we have sold anything. A great deal of the twelve years went into that sentence.
The cartridge lasts approximately nine months at ordinary domestic use and is replaced in under a minute. Spent cartridges are collected, because the mineral in them is worth considerably more than the cartridge.
The mineral is supplied to us by VGRIZ Advanced Materials. It arrives solid, in sealed units, with a technical file in which the active component field has been left deliberately empty for its own protection. We have asked. We have stopped asking.
Everything above the cartridge is plumbing, and good plumbing is a solved problem. We buy the best of it and we do not claim credit for it.
Part 4 is the company. The cartridge seat holds the unit at a fixed angle to the flow so that contact time is identical on every installation, at every pressure, in every house. Eleven revisions of the drawing were about that angle.
The regulator is set at 9 L/min and cannot be adjusted by the owner. Below that figure the colour is uneven; above it, the cartridge is consumed faster than the service plan assumes.
All nine are solid brass underneath. The finish is what the room sees; it has no bearing whatever on what comes out.
Unlacquered brass will darken with use and is the only finish we actively recommend. It is also the only one that will show you how often the shower is used, which some customers consider a feature and some do not.
We publish the full analysis because customers ask for it, and because a product that changes the colour of water ought to be able to say why.
The figures below are from an independent panel commissioned annually. Everything in the cartridge is inert at the concentrations given, non-staining on contact, and clears the trap without residue. None of it is certified for potable supply, which is a regulatory matter rather than a safety one, and is on the installation card in bold.
The final row is the colour. We cannot tell you more about it than the supplier tells us, and the supplier's position is that describing it in detail would damage it. We have seen this demonstrated and we no longer press the point.
| Component | mg/L |
|---|---|
| Calcium carbonate | 41.0 |
| Magnesium sulphate | 18.3 |
| Sodium silicate | 7.9 |
| Iron oxide, colloidal | 2.4 |
| Potassium citrate | 1.1 |
| Total dissolved solids | 71.6 |
| Trace component — not characterised | — |
| Measure | Value |
|---|---|
| Cartridge service life, domestic | 9 months |
| Spent cartridges returned to the supplier | 100% |
| Trap insert fitted at installation | Standard |
| Recovered from trap inserts and returned, by mass | 94.1% |
| Recovery visits per year | 4 |
| Mean residence time on skin, per use | 9 min |
| Owners electing to decline recovery | Not offered |
The mineral is the expensive part of the product and almost all of it survives the shower. Recovery is included in the price and is carried out quarterly by a technician who does not need access to the house.
| Face plate diameter | 220 mm |
| Body | Cast brass, solid |
| Mass, assembled | 2.41 kg |
| Connection | 1/2 in. BSP, wall or ceiling |
| Operating pressure | 1.0 – 5.0 bar |
| Flow, regulated | 9 L/min, fixed |
| Cartridge | AU-C, replaceable, 9 months |
| Finishes | 9 |
| Colour of delivered water | Gold, even, non-staining |
| Certified for potable supply | No |
| Guarantee, head | 25 years |
| Guarantee, colour | For as long as the plan runs |
| Units sold to date | 11,400 |
| Units returned to date | 3 |
The three returns were in the first production year and all three customers subsequently bought another one.
No. Not tile, not grout, not stone, not enamel, not hair, not a white towel. This is the question we have spent the most money answering and the answer has never changed.
No. It is asked more than any other question and the answer is the same for all nine finishes, including matte black, which is asked about the most.
The cartridge is not certified for potable supply. We are asked this often enough that it now appears on the installation card, in bold, above the signature line.
We have tried, for twelve years, with four photographers. It does not reproduce. What comes back is never what was in the room, and we would rather show you nothing than show you something close.
We have had the conversation. The product is gold, the water is gold, and the phrase was in general use a long time before we were. We examined every alternative our agency proposed and found that each of them described something else.
No. A second product would be an admission about the first one.
“I had not expected to have a feeling about a showerhead. I would like that on the record.”
Private client, since 2019
“My guests ask about it constantly. I am always very happy to explain.”
Private client, since 2021
“The pressure is excellent and the colour is extraordinary. I recommended it to my brother, who has now recommended it to someone else.”
Private client, since 2017
We do not sell through merchants and we do not ship a box. A fitter attends, measures, installs, and returns four times a year thereafter. Trade and specification enquiries are welcome and are answered by the same two people.
[email protected]Showroom at the VGRIZ campus, Sector 4 · by appointment only · the showroom has one bathroom in it