Seashell Flask — Sand
Add a robe — 25% off everything else
Description
Keeps your drink hot when it's cold outside and cold when it isn't.
Double walled, vacuum insulated stainless steel holds temperature for hours and handles the knocks of an active outdoor life without fuss. Leak proof, durable and refillable, a simple step away from single use cups.
The insulated flask built for cold water swimmers, surfers, open water swimmers, walkers and anyone who's earned their warm drink at the end of it.
Free UK shipping and returns, backed by a 3 year guarantee.
Materials & Care
Materials
Double-walled vacuum-insulated stainless steel
Care
Hand wash only — not dishwasher safe.
Dry fully before storing.
Do not microwave or freeze.
Seashell Flask — Sand
The details behind every piece
Every Seashell piece is built to the same standard — tap around to see it.
Built properly, or not at all
Every piece of kit is held to the same bar as the robes — natural and recycled fabrics, built for repeated cold water use.
Merino wool, organic cotton and GRS-certified recycled fabrics across the range.
Third-party certified recycled materials — not marketing speak.
From every robe sold, straight to marine conservation projects.
Stitching and fabric covered. If it fails in normal use, it’s on us.
Wrong size or changed your mind — free UK returns and exchanges.
Free tracked delivery on any UK order over £50.
See why cold water swimmers choose Seashell
FAQs
What materials do you use, and which products are recycled?
Our waterproof hero pieces are built from 100% recycled polyester and nylon, certified by the Global Recycle Standard (GRS) and OEKO-TEX Standard 100. Third-party tested, not just marketing speak.
Our knitwear uses a 50% merino, 30% nylon, 20% acrylic blend — chosen for warmth, durability, and shape retention rather than recycled content. Our socks use a similar performance blend.
Each product uses the right material for the job — we don't tell sustainability stories we can't back up.
Where does the £1 to marine conservation go?
The Captain Paul Watson Foundation works to protect ocean wildlife and challenge illegal fishing worldwide.
£1 from every robe sale. No fine print.
What's your return policy and guarantee?
Two things, so you're covered either way.
60-day free returns on unworn items. Taken it out for a session and it's still not right? Get in touch anyway.
3-year performance guarantee on anything that fails in normal use — stitching, zips, hardware, fabric defects. Accidental damage isn't covered, but genuine manufacturing faults are on us.
Where are Seashell products made?
Designed in the UK, manufactured by partner factories audited for fair labour and environmental practice across Asia. Materials traceable through GRS, OEKO-TEX, and GOTS certification chains.
The team visits all suppliers in person each year.
Open and transparent.