Sourcing replacement flask liners from China

Zero duty, with glass inners excluded

Read from the UK Trade Tariff on 30 September 2026, heading 9617 covers complete vacuum flasks and other vacuum vessels, and their parts other than glass inners. Qualifying replacement liners from China carry 0% duty. The supplied tariff record lists no anti-dumping or countervailing measure, suspension or attached import control.

The supplied data contains only the commodity line shown in the table. Its rate must not be applied to replacement glass inners, which the heading explicitly excludes. Send your broker the material specification, construction drawing and photographs to confirm the commodity code. For other replacement parts within the heading, see replacement flask stoppers.

Specify the liner against the flask body

Start with the material and an approved flask body. Specify overall height, body diameter, neck profile, mouth finish, locating shoulder and base support. Identify the intended flask models and supply matching bodies, stoppers and seals for assembly trials. Agree dimensional tolerances on a drawing rather than ordering by nominal capacity alone.

For metal liners, specify the steel grade, wall construction, weld finish and how the vacuum is sealed. Ask for food contact migration reports covering the supplied construction and intended hot-drink use, including any supplied seals. Agree the heat retention test method and test the replacement liner fitted into its intended flask.

Consumer products sold in Great Britain must be safe in normal or reasonably foreseeable use. Include fitting trials, checks for sharp mouth edges and secure seating in your purchasing specification.

Worked duty example

Illustrative example, not a quote: Illustrative order: 2,500 stainless steel replacement vacuum flask liners under 9617 00 00 00, invoiced at £10,000 free on board, with £2,500 of freight and insurance to the UK. The customs value is £12,500. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £12,500, so it is £2,500. With no duty, the only import tax is the VAT, which a VAT-registered importer can usually reclaim. The import duty and VAT guide explains each step.

Inspection checklist

Fit: assemble sampled liners in the agreed flask bodies; check neck alignment, base seating, seal compression and stopper closure without forcing parts.

Vacuum and welds: inspect seams and the vacuum closure; test assembled heat retention against the approved method and check for unexpected outer-wall heating.

Drink-contact surfaces: compare material certificates and migration reports with the supplied liner; inspect for rough welds, contamination and exposed sealing materials.

Arrival condition: check for dents, distorted mouths and damaged supports; confirm protective packing and model identification against the order. Set these checks out in the inspection brief.

What goes wrong

A liner can match the advertised capacity yet fail to fit the body. A different neck shoulder or base position can prevent the stopper sealing or leave the liner loose. Approve an assembled sample with the actual body and closure before releasing production.

Poor welds or a failed vacuum seal reduce heat retention. Dented mouths can spoil sealing, and reports for a complete flask may not identify the replacement liner being supplied. Compare the delivered construction with the approved sample and repeat assembled performance checks on arrival.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For own-brand ranges, see sourcing for brands.