This page is the analysis. What a wider pressing surface does to the force a pump needs — which is less than people expect — and what it changes instead.
The numbers it argues from were measured rather than assumed, and the measurement has its own page: how much force a soap pump takes, on three supermarket bottles. Start there if you want the readings and the method before the argument.
This page shows the sums. Everything here is either worked out from the drawings, quoted from someone else, or marked as unknown, and each number says which. The sums came first and the measurement came after: a real pump takes about 28 newtons, and fitting the disc did not change that. Argument and measurement agree, and section 4 sets out what was found.
In plain words, and it does us no favours.
The PALM does not make a stiff pump easier to push. It has no lever in it. Push it and you push the pump just as hard as before.
What it does is give you a bigger thing to push. The pump top is about the size of a 5p coin. The PALM is about the size of a drinks coaster. That is the whole trick.
Why that helps some people: a big flat top lets you push with your palm, your fist or your forearm. A small one only really lets you push with a fingertip — and a fingertip has only the small muscles of the hand behind it, where a palm has your arm and your weight. If your palm is stronger than your fingertip, or your fingertip hurts, the swap is worth something. If it isn't, it isn't — and you know your hands better than we do.
Force and pressure are not the same thing, and it matters here.
Force is how hard you push. Pressure is how hard you push spread over the area you push with.
Stand on the floor in trainers and it's fine. Stand on the same floor in stiletto heels and you dent it. Your weight — the force — never changed. All that changed was how much floor it was spread over.
A soap pump is the stiletto. A PALM is the trainer. Same push. Spread wider.
Every dimension below is transcribed from handl's own engineering files — RANGE_SPEC.md and the parametric CAD source the parts are built from. The arithmetic is in a script anyone can run, and it reproduces the engineering notes' own figures to 0.1 mm, which is the only reason to believe the rest of the table.
On this page
1. It has no lever in it
Some tools make a job easier by using a lever. A spanner. A bottle opener. You move a long handle a little way, and the short end pushes hard. Engineers call that mechanical advantage.
The PALM has none of that. It is a flat plate that sits on the pump top. No hinge, no handle.
The handl design notes put it in one line: “Press load runs disc → top of the head.” Your push goes straight through. Nothing multiplies it.
So the sum is simple. Push in equals push out. Mechanical advantage: 1. (Calculated, from the way the part is built.)
Your pump needs about a 28 newton push — that is the measured figure, roughly the weight of a 3 kg bag of potatoes. Put a PALM on it and it still needs about a 28 newton push.
If your pump is simply too stiff, this will not fix that. A foaming dispenser or a wall lever will. We sell neither. Both are on the comparison page.
2. What does change: how much room you have to push
The PALM disc is 62 mm across. About the size of a drinks coaster.
The pump tops it holds are 16.6 to 20.6 mm across for Standard and 21.7 to 25.3 mm for Wide. Section 3 below is where those figures come from, and why they are narrower than the slot itself.
We took the sixteen grooves and the stamped logo off the total before working out the area, even though your hand bridges over both. That makes our figure a bit low rather than a bit high, which is the safer way round. It leaves about 2,510 square millimetres to push on.
| Pump head across | Head area | Disc ÷ head, by area | By width |
|---|---|---|---|
| 16.6 mm | 216 mm² | ~12× | 3.7× |
| 18.6 mm | 272 mm² | ~9× | 3.3× |
| 20.6 mm | 333 mm² | ~7.5× | 3.0× |
| 21.7 mm | 370 mm² | ~6.8× | 2.9× |
| 25.3 mm | 503 mm² | ~5× | 2.5× |
So the PALM gives you 5 to 12 times as much room to push on, depending on your pump. It used to say 4 to 17 here, which was worked out across 13.5 to 28.1 mm — the full length of the slot, including the parts of it that do not hold a top at all. Whether it is 4 times or 17 depends on the pump top you have, which takes a minute to measure. The disc itself is £9.99.
Spread the same push over more room and the pressure drops by the same amount. That is the trainers and stilettos again, in numbers.
This only works if you actually use more of your hand.
Poke the middle of the disc with one fingertip and nothing has improved. That fingertip is still doing all the work, and it still hurts.
The extra room is a chance to use your palm or your forearm. It does not happen on its own.
And we have not measured how much of a real hand touches the disc. We would be guessing.
3. The disc often sits off to one side
This is a real drawback, so here it is.
Standard and Wide have a slot underneath that gets narrower towards one end. Your pump top slides in and stops where the slot gets too tight for it. A small top slides a long way in. A big top stops sooner.
Which is why Standard and Wide go on spout first: hold PALM level, put the wide opening of the slot over the spout end of the pump head, then slide PALM back along the head until it grips. It goes on sideways, not down from above. Starting at the back of the head presents the narrow end of the slot to the widest part of the head, so it will not seat — and that reads exactly like the wrong size when it is not.
Everything on this page about wedges and offsets is about those two. The Dome has no slot and does not slide on at all — it grips past the widest point of a rounded head instead. Place it over the head, then press it all the way down until soap comes through the spout. That one full press is what seats it, and a Dome pushed on lightly will sit loose and rock.
That means the disc is usually not sitting neatly on top of your pump. It is off to one side.
We worked out how far. A 20.6 mm pump top ends up 12.2 mm off centre — about the width of a finger. The handl design notes worked this out separately and got 12.2 mm too. Two sums agreeing is the reason to trust the rest of this page.
| Head across | Offset from disc centre | What that means |
|---|---|---|
| 13.5 mm | 31 mm | Out at the far rim. Not sold for this — the disc becomes a lever |
| 16.6 mm | 12.2 mm | Standard starts here |
| 18.6 mm | 0 mm | Dead centre. The best case |
| 20.6 mm | 12.2 mm | Standard stops here. The furthest off centre we will sell |
What that means for you: push down over the pump, not out at the edge of the disc. Push the edge and you tip it instead of pressing it. It is like pressing the corner of a light switch rather than the middle.
This is what sets the sizes we sell. A top sits best when it wedges near the middle of the slot; the further from the middle it seats, the nearer the rim the press lands. We have drawn the line at 12.2 mm off centre and mirrored it either side of the dead-centre width, which gives Standard 16.6 to 20.6 mm and Wide, which sits dead centre on 23.5 mm, 21.7 to 25.3 mm. Be clear about what that 12.2 mm is: a cautious choice, not a measured limit. It is the offset of the 20.6 mm row in the table above, and nobody has yet measured, on a real pump, how far off centre a top can seat before a press tips it. The slots run wider than the bands — Standard’s from 23.7 down to 13.5 mm, Wide’s from 28.1 down to 18.9 mm — so taken as slots the two sizes overlap, from 18.9 to 23.7 mm. The 20.6 to 21.7 mm strip between the bands is a strip we do not sell a stock part for, not one we have shown neither part can hold. A different line would move the bands, and a looser one would make them meet. Until a pump head has been measured we sell against the narrower bands, because the cost of guessing wide is a part that tips. Before September 2026 the site published the whole slot as the band — which is how a 14 mm top was told to buy a Standard.
Will it come off when you press? No. The slot walls slope at about 4 to 5 degrees. Plastic sliding on plastic grips rather than slips at anything under about 10 degrees, so pushing wedges it on tighter. Dome works differently: it is a split ring that snaps round the fattest part of a round top and holds underneath.
All of that is worked out on paper. The fit itself was tested by hand, on a few bottles, at home.
4. What a pump actually needs — measured
This is the number everything else rests on. It has now been measured.
We looked for a published figure first. All we found were figures inside patents, which are what a designer hoped for rather than what a real bottle does, and numbers in makers' own adverts. Nothing independent. Nothing that lets you compare one brand with another. Nothing at all for the bottles you can buy in a supermarket.
So we measured it, and published it on 22 August 2026 in the guide on how much force a soap pump takes. Three supermarket hand soaps — Cussons, Baylis & Harding and Carex — each pressed on a kitchen scale once by each of two people. The six bare readings run from 27.4 to 29.2 N and average 28.31 N. About 28 newtons is the working figure. The method, the raw table and the limitations are on that page. That page is how much force a soap pump takes.
Two results there matter to this one. The three brands sit within 6% of each other, so 28 N is a property of a supermarket pump rather than of one bottle. And the two people got the same reading on every bottle — 1.29% apart at the widest — so the force belongs to the pump and not to the hand on it. That is why “press harder” is not advice.
The Cussons was pressed once more with a PALM fitted: 2,938 g against 2,944 g bare. That is 0.20% — a smaller gap than the 1.29% between the two people pressing the same bare bottle. The measurement agrees with the mechanical advantage of 1 above. The disc does not take force off a pump. What a pump asks for is the same number whether one is fitted or not.
5. What published data says about hands
This part is somebody else's work, and it is about people in general. It is not a claim about our product.
The standard study of adult hand strength is Mathiowetz and colleagues, 1985. They measured 310 men and 328 women, aged 20 to 94. Grip was measured on one gauge and pinch on another. Occupational therapists have used it for forty years.
Full reference: Mathiowetz V and others, “Grip and pinch strength: normative data for adults”, Archives of Physical Medicine and Rehabilitation, 1985; 66(2):69–74.
Two things in it matter here. We quote what they found, not their tables of numbers, because we could not get the tables in a form we could check:
- Grip and pinch are two different things. They are measured on two different gauges, and one does not predict the other.
- They fade at different times of life. Grip is strongest between 25 and 39. Pinch holds fairly steady from 20 to 59, then slowly drops.
So this is a question for you rather than a claim from us. Is your whole hand stronger than your fingertip? If it is, a wider top lets you use the stronger one.
You can test that today, for nothing. Go and press your own soap pump with the flat of your hand instead of a finger. Your own bathroom will tell you more than this page can.
We have deliberately not quoted specific kilogram figures from that paper. We could not obtain the tables in a verifiable form, and a normative value repeated from a secondary source is exactly the kind of number that gets quoted back at you later.
6. What it is made of
Bambu Lab PLA Pure, in white. PLA is a plastic made from plants — corn and sugarcane — instead of from oil.
Its maker says it has only five ingredients, and lists them: the plant plastic itself; an acrylate copolymer, the sort used in children's toys; colour pigments; a slip agent called ethylene bis-stearamide; and talc that has been checked to be free of asbestos.
What is certified, and what is not
This difference matters, so we will be blunt about it.
- The plastic is certified. Its maker had each of those five ingredients checked against EU 10/2011, the European rules for plastics that touch food, and EN 71-3, the toy safety standard. It also holds UL GREENGUARD, which is about indoor air. Those are facts about the filament on the spool. The finished printed part is not certified as anything: printed parts have layer lines that hold moisture and soap.
- The finished PALM is certified as nothing at all. A certified plastic does not make a certified part. Printed parts have fine ridges that hold water and soap, our printing is not a food-standard process, and nobody has tested a finished one. So we do not say PALM is food safe, food grade, medical grade, antibacterial or sterile. It is a lid for a soap pump, not something to eat off.
- Wash it by hand, in warm water. The plastic goes soft above 60 °C. No hot water, and never the dishwasher.
Is it vegan?
Kareem's own answer, and he is the one making it: I do not know, so I am not claiming it. Nobody has certified it as vegan, and I am not going to be the first to say it.
We can be firmer about four of the five ingredients. The plastic comes from corn and sugarcane. The acrylate copolymer is man-made. The talc is a mineral. Pigments of this kind are minerals or man-made. None of those comes from an animal.
The fifth one we cannot vouch for. Ethylene bis-stearamide is made from stearic acid, and industry makes stearic acid from either plant fats or animal fats. Bambu Lab does not say which they use. So we will not tell you the material is free of animal ingredients, because we do not know that.
Kareem has asked the supplier. If they confirm it, this page will say so and name them. Until then: plant-based, not certified, and one ingredient we cannot account for. We would rather give you that than a badge.
7. The other things that are true about it
This page is about force, and on force the honest answer is that the part does nothing. So that it is not the only thing you take away, here are the other properties — all of them measurements of an object rather than claims about a person.
- 62 mm across, 10.5 mm thick (16.5 mm for the Dome).
- Clips on and off in seconds, by hand, with no tools.
- Moves between bottles whose tops are in range.
- Fits in a bag, so it works away from home.
- Nothing to refill, no batteries, no wall fixing.
- Leaves the bottle looking like the bottle, rather than replacing it with a piece of equipment.
Those are the reasons to choose it over the alternatives on the comparison page. The force is not one of them.
8. Status of every number on this page
| Figure | Status |
|---|---|
| Disc 62.0 mm, channel widths, lip, wedge angles, lip circle | Design values, from handl's CAD source |
| Mechanical advantage = 1 | Calculated from the load path |
| Areas, area ratios, wedge offsets | Calculated — rigid body, ideal contact, friction ignored, circular approximation for the head |
| Self-locking band 10–16° | Cited from handl's own design rules |
| Hand strength findings | Cited — Mathiowetz et al. 1985 |
| Material certifications | Cited — the filament manufacturer, for the filament only |
| Force any pump needs | Measured. Our own readings, six bare presses on three supermarket bottles: 27.4 to 29.2 N, mean 28.31 N. Corroborated by independent load-frame readings on four other bottles, 12.75 to 37.27 N |
| Contact patch of a real hand | Unknown. Not measured |
| Fit on real bottles | Measured informally — by one person, on his own bottles, at home. Three confirmed: Baylis & Harding Signature, PZ Cussons hand wash, one decorative dispenser |
PALM was designed by one person for his own use, because he could not press the pump in his own bathroom. It has not been through any trial, test programme or certification, and no clinician has assessed it. It is offered on the reasoning that a mechanism which helps one pair of hands may help others with similar difficulty, even where the underlying reason is completely different. That is the whole claim, and we would rather make that one honestly than a bigger one we cannot support.
That is exactly what it does and exactly what it does not do: no lever, no mechanical advantage, a much bigger place to push. If that is the trade you want, here it is.
Where to get proper help
A pharmacist will talk to you about hand pain with no appointment and no referral. An occupational therapist looks at your hands and your kitchen rather than at a category page, and in England you can ask your council for an assessment. Both are free. Living Made Easy, run by the Disabled Living Foundation, is an impartial database of daily-living equipment that lists our competitors alongside us. The fuller list adds the charity helplines.
PALM is a daily-living aid, not a medical device. It does not treat, prevent or improve any condition, and nothing here is medical advice.