FAQ
The questions we actually get asked, answered in full — including the ones where the honest answer is not the flattering one. If yours is not here, ask us and we will add it.
Materials & claims
Is there a coating or an inner lining?
No. Two materials, and we name them both: 304 food-grade stainless steel, and one food-grade silicone seal. No coating, no liner, no third material. The bottle is the one exception worth naming — see the question below.
Is there a coating or an inner lining on the bottle?
No coating and no liner. Every surface your water touches is 304 food-grade steel — the inner wall and the inside of the cap — plus one food-grade silicone ring. The outer skin your hand holds is 201 steel, a lower grade, and it touches nothing you drink. We'd rather name it than round down.
Is the lid plastic?
No. The lid is 304 stainless steel, the same as the body. This is the whole reason the brand exists: in the Netherlands every serious rival closes with polypropylene, whatever the box is made of.
Is the bottle cap plastic?
No. The cap is stainless steel, with one food-grade silicone ring so it seals. There is no plastic liner disc inside it either — we checked, because almost every other steel bottle has one.
So your containers aren't really plastic-free?
Correct, and we would never say they were. There are two materials in everything we make: 304 stainless steel and one food-grade silicone seal. Silicone is not a plastic, but it is not steel either, so we name it rather than round down to one.
Is silicone a plastic?
No, though we understand why the question comes up. Silicone is a synthetic polymer built on silicon and oxygen rather than on carbon chains from oil. It is stable across a wide temperature range and has a long record in kitchens and cookware. It is also the one part of our product that wears out, which is why we sell spares.
Is it BPA-free?
There is no plastic in our containers, so there is nothing here for BPA to be in. We don't print the phrase on anything, though. 'BPA-free' was the last reassurance the industry offered, and it expired — BPA got removed and quietly replaced with a different bisphenol.
304 or 316 — which do I have?
304, also written 18/8, in every product at every size and every price. 316 is a marine grade: its advantage is resistance to chloride corrosion, which matters on a boat or in a salt spray. It is not a food-safety difference, and any brand implying otherwise is selling you the number, not the benefit.
Is stainless steel actually food safe?
304 has been the standard in professional kitchens, food processing and brewing for decades, and it is what EU food-contact rules are written around. That is not the same as a certificate with your name on it, so if you want the specific reassurance, ask us and we will tell you exactly what we hold.
Can stainless steel release chemicals into food?
Trace amounts of nickel and chromium can migrate from steel into food — that is measured and real. The research showing meaningful amounts is about cooking: hours of simmering acidic food at heat. No study we can find has measured cold storage in a fridge over days. So we are not going to tell you steel doesn't leach, because nobody can honestly prove that negative.
What if I have a nickel allergy?
Around 10–15% of people have some nickel sensitivity, usually as contact dermatitis on skin. 304 contains roughly 8% nickel. Migration into stored food is trace-level, but if you are highly sensitive, that is a decision to make with a doctor rather than with us.
Is metal really better than glass?
Not better — different. Glass wins the oven, the microwave, the table and the price, and you can see through it. Steel wins the drop, the bag and the decade. If your container mostly lives on a shelf and goes into an oven, buy glass. If it gets carried, buy steel.
Heat, cold & the microwave
Can I put it in the microwave?
No. Metal does not go in a microwave — not ours, not anybody's. This is the one real trade-off in owning steel and we would rather you knew it before you bought than after.
How do I heat food without a microwave?
A pan on the hob for anything with sauce, an oven dish for anything baked, a plate over a pan of simmering water for rice and grains. It takes a few minutes longer and it reheats better — a microwave heats unevenly and turns the edges of leftovers rubbery.
Can I put hot soup in it?
Yes, but let it cool a little before you close the lid. Hot food sealed in a container cools, the air inside contracts, and the pressure difference works against the seal — that is the most common cause of a leak in a bag.
Can I put it in the freezer?
Yes. Steel handles cold without going brittle and it will not crack the way glass can. Leave a couple of centimetres of headspace so the food has room to expand as it freezes.
Can it go from the freezer straight into the oven?
No — because we don't recommend the oven at all, tested or not. Thaw in the fridge overnight and reheat in a pan or an oven dish.
Does it crack or warp when frozen?
No. Steel doesn't become brittle at freezer temperatures the way plastic does, and it doesn't shatter the way glass can. The only thing to watch is headspace: food expands as it freezes and it needs somewhere to go.
Does the silicone ring survive the freezer?
Yes. Silicone stays flexible far below freezing. Repeated freeze cycles will shorten its life the same way dishwasher cycles do — that is why it is a consumable and why we keep spares in stock.
Does metal cause freezer burn?
No. Freezer burn comes from air reaching the food, not from the material around it. A container that closes well and isn't half empty is the whole answer — steel or otherwise.
Does the bottle keep drinks cold, and for how long?
It is double-walled, not vacuum-insulated. That means the outer wall stays dry so it doesn't sweat in your bag — but it is not a flask and it will not hold your coffee hot all day. If you want vacuum insulation, buy a vacuum flask; we would rather say so than let you find out at lunchtime.
Does water condense on the outside of the bottle?
Much less than on a single-wall bottle — the air gap between the two walls means the outside stays close to room temperature, so there's no damp patch in your bag and no ring on your desk. It is not vacuum-sealed, so on a hot day with ice water you may still see a little.
Leaks & carrying
Is it leakproof?
Leak-resistant, and we won't say leakproof. Upright in a bag or a fridge it holds. On its side with soup in it, we wouldn't bet on it. The seal is silicone and silicone wears out, so a container that sealed perfectly in year one may weep in year four — which is why we sell replacement seals rather than pretending the problem doesn't exist.
Can it lie on its side in a bag?
For anything dry or solid, yes. For soup, dressing or yoghurt, we'd keep it upright. Leak-resistant means the seal handles pressure and movement; it does not mean you can carry liquid sideways for an hour and expect nothing.
The lid is stiff after the fridge. Why?
Warm food sealed in a container cools down, the air inside contracts, and you end up with a slight vacuum holding the lid shut. Run the rim under warm water for a few seconds and it releases. Letting food cool before you seal it prevents it.
Will the lid still be as tight after a year?
The steel and the clips will be. The silicone seal compresses over time and eventually stops springing back — for most people that is a few years of daily use. A new seal costs a few euros and restores it.
Will it dent if I drop it?
Yes, if it lands on a hard floor. Steel dents where glass shatters and plastic cracks. A dented container still closes and still works — it just carries the evidence. We're not promising it will look new in 2036; we're promising it will still be steel.
Cleaning & care
Is it dishwasher safe?
Yes, all of it. Lids on the top rack. Let everything dry fully before storing — steel doesn't mind water, but water left standing leaves lime marks.
How do I clean the lid — does the ring come out?
The silicone seal lifts out of its channel with a fingernail. Take it out every few weeks, rinse both parts, and let them dry completely before you put the seal back. That one habit prevents almost every smell and residue problem people have with sealed containers.
How do I get baked-on food out?
Hot water and a few minutes of soaking does most of it. For the rest, a paste of baking soda and water and a normal sponge. Steel takes far more scrubbing than a coated pan, because there is no coating to ruin.
Can I use a scourer?
You can, and it will leave fine scratches on the finish. There is no coating to remove and nothing underneath to expose, so it is a cosmetic decision, not a safety one. A normal sponge and a soak usually does the job anyway.
How do I clean the inside of a narrow bottle?
The mouth is wide enough for a hand or a normal bottle brush. For a deeper clean: warm water, a spoon of baking soda, leave it an hour, rinse. Take the silicone ring out of the cap separately — that is where anything lingers, not in the bottle.
Can mould grow under the silicone rim?
It can, in any sealed container of any material, if the seal is left wet and closed. It is the reason we tell you to take the seal out and dry it. Steel doesn't prevent it — nothing does except drying.
Do I get limescale or dishwasher spots?
Sometimes, especially in hard water areas. It is deposit from the water, not damage to the steel. A little white vinegar on a cloth takes it off.
Can I use bleach, soda or vinegar?
Vinegar and baking soda, yes. Bleach, no — chlorine-based cleaners attack the chromium layer that makes stainless steel stainless. That is the one cleaning product we would keep away from it.
Will it rust? Can I leave it wet?
Rarely, and we won't say never. 304 is highly corrosion-resistant because chromium forms a protective layer on the surface. Leaving it wet in a drawer, or attacking it with bleach, is how you get around that. Rust is covered by the ten-year guarantee.
Will it scratch?
Yes. Steel scratches — a fork, a brush and a dishwasher rack all leave marks eventually. The difference is what a scratch means. In plastic it is somewhere for oils and colour to settle. In steel it is cosmetic and nothing else.
Is it noisy, or will it scratch my worktop?
It is metal on a hard surface, so it is louder than plastic. On stone or laminate it won't mark anything; on a soft or coated worktop, put it down rather than sliding it, as you would a pan.
Taste, odour & food safety
Does it hold on to smells?
No. Steel is non-porous, so garlic, curry and fish don't stay behind the way they do in plastic. The one place odour can linger is the silicone seal — take it out and wash it separately now and then.
Does it give food a metallic taste?
No. Water out of a 304 steel bottle tastes like water, and food stored in a steel container tastes like food. If you notice a taste, it is almost always the silicone seal holding something from a previous meal — take it out and wash it.
Will tomato, turmeric or beetroot stain it?
Turmeric and tomato can leave a faint tint on the silicone seal. The steel itself doesn't take colour the way plastic does — this is one of the clearest everyday differences between the two materials.
Does acidic food react with the steel?
For normal storage, no problem — tomato, citrus and vinegar dressings in the fridge overnight or for a few days are exactly what these containers are for. The research showing measurable metal transfer is about cooking: hours of simmering at heat, not a box in a fridge.
Does food stay fresh as long as it does in plastic?
About the same. Shelf life comes from the seal, not the material — a good silicone ring keeps air out whether there is steel or plastic around it. What steel does add is opacity: no light reaches the food, which genuinely matters for nuts, coffee and wholegrain flour.
Does a slimy film form inside the bottle?
It can, in any bottle, if you refill it for days without washing it — that film is biofilm and it forms on steel as readily as on plastic. Rinse it daily and wash it properly once a week and you'll never see it.
Sizes, weight & storage
What are the exact dimensions?
Rectangular 800 ml: 170 × 120 × 60 mm. Rectangular 1400 ml: 215 × 165 × 60 mm. Round 480 ml: Ø 115 × 66 mm including the lid. Round 1200 ml: Ø 155 × 90 mm including the lid. Bottle 500 ml: Ø 70 × 220 mm.
How heavy is it in a bag?
Empty: 480 ml is 146 g, bottle 271 g, 800 ml 275 g, 1200 ml 292 g, 1400 ml 381 g. Heavier than plastic, lighter than glass. In a backpack you notice it. In a fridge you don't.
I can't see what's inside. How do I keep track?
You can't see through it, and that is a genuine trade-off with no fix in the product. What works: put the newest thing at the back, keep one size for one job, and use a food-safe chalk marker on the lid — it wipes straight off steel. Glass is the honest answer if seeing the contents is the whole point of your fridge.
Do I have to replace everything, or can I start small?
Start small. Most people replace the two or three containers they actually use every day and leave the rest of the drawer alone until it wears out. The Starter Set exists for exactly that; the singles exist for people who want to try one first.
How long does this really last?
We guarantee the steel for ten years, and we don't advertise past our own warranty. The silicone seal is the part that wears out — a few years of daily use — and a new one costs a few euros.
Guarantee & spare parts
What if the lid breaks?
The lid is steel and it is covered for ten years like everything else steel. If the lid stops sealing, that is almost always the silicone seal rather than the lid — and a replacement seal costs a few euros.
What does the ten-year guarantee cover?
Ten years on the steel: body, lid, divider, bottle and cap. Rust included. If it rusts through, cracks or wears out, we replace it. This sits on top of your statutory rights under Dutch and EU consumer law.
Why isn't the silicone seal covered?
Because silicone wears out, and we would rather tell you than let you find out. After a few years of dishwasher cycles it compresses and stops springing back. That isn't a defect — it is what silicone does. So we sell you a new one for a few euros instead of guaranteeing something we know will fail.
My lid has stopped sealing. What now?
It is almost certainly the seal, and it is almost certainly not broken — just compressed. Lift it out, check it springs back when you squeeze it, and if it doesn't, order a replacement. Choose the size that matches the product you own; a 480 ml seal will not fit a 1200 ml lid.
Can I reorder individual parts?
Seals and rings, yes — always, for as long as you own the product. Lids and bodies are not sold separately; if a steel part fails within ten years it is a guarantee claim, not a purchase.
How do I claim on the guarantee?
Email hello@thestainless.co with your order number and a photo. That is the whole process.
Ordering, delivery & returns
How fast is delivery?
Order before 12:00 on a weekday and it ships the same day. Delivery takes 1–3 business days in the Netherlands and 3–7 in the rest of the EU. Shipping within the Netherlands is €6.95, free from €70.
How much does shipping cost?
Netherlands €6.95, free from €70. Belgium, Germany, France and Luxembourg €12.95. Rest of the EU €15.95, Malta and Cyprus €24.95. Outside the EU, the cost is shown at checkout.
Will I pay import duties or extra costs?
Within the Netherlands and the EU, no — the price you see includes VAT and there is nothing to pay on arrival. Outside the EU, import duties are set by your country and are the customer's responsibility.
Do you ship internationally?
Yes. Netherlands, the European Union, and a list of countries outside it including the US, UK, Switzerland, Norway and Canada. Available destinations and their rates are shown at checkout.
What is your return policy?
Thirty days to change your mind. Items must be unused and in the original packaging. Thirty is more than the fourteen days EU law requires, because a container is hard to judge from a photograph.
Who pays for return shipping?
You do, unless the item is defective or we sent the wrong thing — then we do.
When will I receive my refund?
Once we have received and checked the return, the refund goes back to your original payment method. Depending on your bank that takes a few working days to appear.
My item arrived damaged or incorrect. What now?
Email hello@thestainless.co with your order number and a photo, and we will sort it. Return shipping is on us in that case.
Can I exchange a product?
The fastest route is to return what you have and place a new order, so you're not waiting on two shipments in sequence.
Can I change or cancel my order?
Email us as soon as possible. We pack quickly, so we can't guarantee it — but if it hasn't shipped we will always try. If it has, use the 30-day return.
How can I track my order?
You get an email with a tracking number when it ships. Tracking can take up to 24 hours to start showing movement.
What if my package is delayed or lost?
Delivery estimates depend on the carrier. If your order is well past its window, email hello@thestainless.co with the order number and we will chase it.
What payment methods do you accept?
The methods available to you are shown at checkout and vary by country. In the Netherlands that includes iDEAL and the major cards.
Where can I find my invoice?
Your order confirmation email is your proof of purchase and carries the full order details. Need a formal invoice with a company name on it? Email us.
About us
Who are you? Is this a real company?
The Stainless Co. is a brand operated by Resoluta B.V., Krachtenveld 61, 3893 CD Zeewolde, the Netherlands. KvK 58835415, Btw NL823795998B01. You can email a person at hello@thestainless.co.
Why is the site in English?
Because we built the brand to work outside the Netherlands too, and the English store came first. The Dutch version is at thestainless.co/nl-nl and we're still filling in the parts that haven't been translated yet. If you hit something in English that should be Dutch, tell us and we'll fix it.
Why is this so much more expensive than plastic?
Because you buy it once. A €25 steel box that lasts ten years costs less per year than a €6 plastic set replaced every eighteen months — and the ten years is a guarantee, not an estimate. If you replace containers rarely and don't mind plastic, the maths won't favour us, and we're not going to pretend otherwise.
Is stainless steel better for the environment?
Not automatically, and we're not going to claim otherwise. The Consumentenbond looked at reusable bottles and found steel ones came out worst on environmental impact, because making steel is energy-intensive. What makes a container sustainable is how long you keep it. Ours is built and guaranteed to be kept.