Stainless King Food Flask Stopper Update

Last updated: 1 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

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

Product Images

Red 470ml Red 710ml