Stainless King Food Flask Stopper Update

Last updated: 11 May 2026

We’re aware of recent product recall announcements in the United States relating to certain Thermos Stainless King products.

This page provides information for UK customers.

Product Update

Thermos UK introduced a new and improved stopper for its 470ml and 710ml Stainless King Food Flasks in 2022.

All Stainless King Food Flasks produced since then feature an enhanced stopper with a pressure relief valve, visible as a small circular detail on the underside of the stopper.

Older Products (Pre-2022)

Stainless King Food Flasks manufactured before 2022 may have an earlier stopper design.

When used in accordance with the manufacturer’s instructions, these products remain safe to use.

This includes guidance not to store food or drink in the flask for longer than 24 hours.

UK Safety Position

  • We are aware of reported incidents in the United States.
  • There have been no recorded cases of personal injury in the UK related to these products.
  • No other Thermos UK products have used this stopper design.

Replacement Option

If you own a 470ml or 710ml Stainless King Food Flask manufactured before 2022 and would prefer to receive a replacement stopper, we’re happy to help.

Please contact our Customer Service team:

Email: Customer.service@thermos.co.uk

To help us process your request more quickly, please include:

  • A photo of your flask
  • A photo of the underside of the stopper
  • The product size (470ml or 710ml, if known)

How to Identify Your Product

  • Product sizes affected: 470ml and 710ml Stainless King Food Flask
  • New stopper (post-2022): has a visible pressure relief valve (small circle underneath)
  • Older stopper: no pressure relief valve

Frequently Asked Questions

Does the US recall apply to the UK?

No recall has been issued in the UK. Thermos UK introduced an updated stopper design in 2022, and we are happy to provide replacement stoppers for customers with older versions of the stopper.

Which Thermos UK products are affected?

Only the following Thermos UK products used this stopper design:

  • Stainless King Food Flask 470ml (SK3000)
  • Stainless King Food Flask 710ml (SK3020)

No other Thermos UK products are affected.

Can I continue using my flask?

Yes, products may continue to be used in accordance with the  care and use instructions.
This includes:

  • Not storing contents for longer than 24 hours
  • Opening the flask carefully
  • Pointing the flask away from the user if pressure build-up is suspected

Why can pressure build up inside the flask?

If food or drink is left inside a sealed container for an extended period of time, pressure can build up naturally.
Thermos care and use instructions advise consumers not to store contents for longer than 24 hours and to open the product carefully if pressure build-up is suspected.

How do I know if I have the newer stopper?

The updated stopper introduced in 2022 includes a visible pressure relief valve on the underside of the stopper.
This appears as a small circular feature in the centre underneath.

I bought my flask outside the UK or from Amazon.com. Can Thermos UK still help?

Yes. If you currently reside in the UK, we can help. Please contact our Customer Service team with details of your product and purchase.

Product Images

Red 470ml Red 710ml