Sourcing brass threaded inserts from China

Duty on brass threaded inserts

Heading 7415 covers copper and copper alloy fasteners, including brass nuts and other threaded articles. For inserts, distinguish articles classified as nuts under 7415 33 00 00 from other threaded articles under 7415 39 00 00. The table repeats the nut line for different insert designs; these are product variants, not separate tariff subdivisions.

Read from the UK Trade Tariff on 5 November 2026, both relevant threaded lines carry 0% duty for goods from China. The supplied tariff record lists no anti-dumping or countervailing duty, suspensions or attached import controls. This tariff position does not establish suitability for the intended application.

Confirm the commodity code using the drawing, material and function before shipment. Brass-plated steel is not solid brass and follows the steel fastener classification described in our copper and brass fasteners guide.

Specify the insert and its plastic housing together

State the brass alloy and composition limits, internal thread and tolerance, body length, outside diameter, flange and blind-hole details, knurl pattern and finish. Identify whether installation uses heat, ultrasonic insertion, pressing or moulding around the insert. Supply the housing material, hole drawing and mating screw details rather than approving the insert in isolation.

Agree installation conditions and acceptance criteria for pull-out, resistance to rotation and repeated screw assembly in the intended plastic. A sample fitted into a different resin or hole geometry does not demonstrate performance in your housing.

UK REACH generally applies to chemical substances in articles. Ask for alloy composition and check applicable restrictions against the intended use. For consumer products children may handle, confirm with HSE whether lead restrictions apply; request supporting material evidence rather than accepting an unspecified brass grade.

Worked duty example

Illustrative example, not a quote: Illustrative batch of brass insert nuts for a small hardware distributor under 7415 33 00 00, invoiced at £4,000 free on board, with £900 of freight and insurance to the UK. The customs value is £4,900. Duty at 0% is £0. Import VAT at 20% is charged on the customs value plus duty, £4,900, so it is £980. 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

Material: compare batch certificates and sample analysis with the ordered alloy; section a sample if plating or a steel core is suspected.

Thread and body: use thread gauges, measure length and outside diameter, and check flange dimensions, thread depth and entry burrs against the drawing.

Installed retention: fit samples into production housings using the agreed process, then check pull-out, rotation and screw assembly against the agreed criteria.

Packing and identity: check that sizes and batches are separated, labels match the packing list, and loose swarf or damaged threads are absent. Plan these checks through our quality inspection guide.

What goes wrong

An insert can pass a thread gauge yet spin or pull out because the knurl, body diameter or housing hole differs from the approved sample. Excess installation heat can distort the plastic; poor alignment leaves the insert tilted. A blind insert can also bottom out the screw before the assembly clamps.

Alloy substitution, burrs and mixed sizes create further failures. Retain an approved insert and housing assembly, compare incoming batches with its drawing, and test installed samples before releasing stock for production.

Cambridge China Bridge sources these products for UK businesses, checking the factory and the documents before shipment. See factory verification. For repeat volumes, see container programmes.