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Birthday Cards That Actually Say Something Rather Good
Look, we understand that birthday cards are rather a minefield. Most of them are frightfully dull, aren't they? Not these ones. Our Mussels birthday cards are properly handsome little things that arrive looking rather fabulous and—this is the bit we're rather proud of—they actually make people smile when they open them.
Why Choose Our Birthday Cards
Gorgeously Printed: Each card is printed on substantial 280gsm card stock, which feels genuinely marvellous in your hands and rather substantial for the occasion.
Environmentally Sound: We've gone to the bother of using sustainable forest sources and vegetable inks, because being kind to the planet shouldn't feel like a chore.
Utterly Fetching Design: These quirky, colourful cards featuring mussels are delightfully stylish without being absurdly pretentious.
Blank Canvas Inside: Room for your own heartfelt (or rather amusing) message without our interference.
Product Details
Dimensions: 120 by 120 millimetres, a perfectly proportioned square format.
Card Quality: 280gsm card stock that feels fabulously made and professional.
Printing: Vegetable-based inks on sustainably sourced card.
Packaging: Arrives wrapped in recyclable sleeves because the planet matters.
Interior: Blank, awaiting your personal touch.
Send something splendid this birthday. These cards arrive looking rather good and genuinely delight the recipient.
SHIPPING + RETURNS
THE RATHER IMPORTANT BITS
This rather lovely piece ships directly from our brand partner - we work with independent brands who are absolutely brilliant and work frightfully hard to create beautiful things.
SHIPPING DESTINATIONS
Now, here's the thing - our wonderful brand partners ship to lots of different places, but not all of them can ship worldwide.
Some are brilliant at international shipping, others prefer to keep things closer to home.
At checkout, you'll see exactly where this particular brand can send your goodies.
We're terribly sorry, but shipping costs do vary rather wildly depending on where you are in the world. The exact figures pop up at checkout - no nasty surprises!
RETURNS
You have 14 days to return items.
Now, we absolutely adore our brand partners - they work incredibly hard and we do try to support them as much as we possibly can. So I'm rather afraid we have to pass the return postage costs back to you. Frightfully sorry about that!
🌍 PLEASE CHOOSE THOUGHTFULLY:
Our wonderful partners put their hearts into everything they make.
Ordering multiple sizes to try at home is rather hard on our planet and makes things jolly difficult for these brilliant independent creators.
When in doubt, do ask us first!
PAYMENT
We're frightfully modern and accept all the usual suspects:
Visa, Mastercard, American Express, PayPal, Apple Pay, Google Pay, and Shop Pay
SECURE AS HOUSES
Everything's properly encrypted and secure - your details are safer than the Crown Jewels!
All prices in lovely British pounds £ GBP, though international chaps will see converted prices.
Any payment pickle? We're here to help sort things out! Contact us
We Have Lots More Like This.........
Hello, we are Sostter....
Sostter began, as all good ideas do, with a lively conversation and a shared sense of frustration. Why had the world of independent design become so serious, so samey, so… beige? Where was the spark, the imagination, the sheer joy of discovering something that made you stop and stare?
We dreamt of a marketplace that celebrated difference — where curious minds could explore a world of independent brands, design-led makers, and thoughtful artisans. A space that felt exciting, human, and beautifully imperfect.
Today, Sostter brings together remarkable people and their creations — from London to Lausanne, Brooklyn to Berlin — uniting makers and discoverers through craftsmanship, creativity, and conscience. Every object tells a story, and every purchase supports an independent brand doing things differently.
This is just the beginning. But enough about us — step inside, explore our world, and see what catches your imagination.
Giving Back
We’re proud to support Sutton Night Watch, a grassroots UK charity making a real difference in the lives of those facing homelessness. Through regular donations of stock, supplies, and essentials, we back their mission to offer warmth, dignity, and practical help to anyone in need — right where it matters most.
Sell with us
Sostter partners with independent brands that intrigue, inspire, and bring something genuinely different to the world of fashion, design, and living.Join us!