| Titanium grade | Confirm the exact grade and whether the cup body is commercially pure titanium or a titanium alloy. Grade 1 and Grade 2 are commonly specified commercially pure grades; do not accept “pure titanium” as the only material description. | Mill test certificate (MTC) identifying grade, chemistry, lot or heat number, and applicable specification. ASTM B265 covers titanium and titanium-alloy sheet, strip, and plate. | The grade affects strength, forming characteristics, and traceability. The certificate should match the material used in the production lot. |
| Material composition | Check that the documented chemical composition falls within the limits for the declared grade. Ask how incoming material is identified and linked to finished products. | Grade-specific MTC and, where appropriate, an independent material identification or chemical analysis report from a competent laboratory. | Helps detect grade substitution and supports batch-level material traceability. |
| Food-contact surfaces | Identify every surface that may contact a drink, including the interior, rim, lid, seal, and any coating or decorative finish. Request documentation for the finished article and its intended conditions of use. | For EU-market articles, review applicable requirements including Regulation (EC) No 1935/2004 and good-manufacturing-practice rules under Regulation (EC) No 2023/2006. Confirm relevant national requirements in the destination market. | Compliance depends on the complete article, intended use, and market—not solely on the name of the base metal. |
| Coatings, inks, and decoration | Ask whether the inside is uncoated. If coatings, inks, adhesives, or printed finishes are used, identify their location, composition, and suitability for the intended food-contact conditions. | Material declarations and migration or other testing selected for the specific coating, food type, temperature, and contact duration. | Additional materials can affect compliance even when the titanium body is correctly specified. |
| Welds and joints | Inspect seams, handle attachments, and rim joints for incomplete fusion, sharp edges, visible cracks, rough areas, or corrosion discoloration. Verify that any filler material is declared where used. | Documented visual inspection criteria, production checks, and sample inspection records; add suitable weld testing when required by the design or risk assessment. | Defects at joints may affect durability, cleanability, and leak resistance. |
| Leak resistance | Agree on a repeatable leak test for the assembled cup and lid, including test orientation, duration, and acceptance criteria. Test representative samples from production. | Written test method and dated inspection records. Treat leak performance as a product specification unless a relevant standard is explicitly agreed. | A cup body may be sound while its lid or seal still leaks during normal use. |
| Dimensions and capacity | Specify nominal capacity, brimful capacity if needed, height, rim diameter, base diameter, and acceptable tolerances. Clarify the measurement method and units. | Approved technical drawing, signed pre-production sample, and inspection results against agreed tolerances. | Clear tolerances reduce disputes about fit, packaging, and usable volume. |
| Surface finish and cleanability | Set acceptance criteria for burrs, sharp edges, dents, scratches, stains, and interior roughness or finish. Check that surfaces are accessible for routine cleaning. | Approved appearance samples, inspection checklist, and agreed defect limits for critical and cosmetic areas. | A consistent finish improves usability and helps prevent avoidable cleaning and handling problems. |
| Lid and seal materials | Request the material specifications for plastic lids, silicone seals, coatings, and other non-metal components. Confirm their intended temperature range and food-contact documentation. | Component declarations, technical data sheets, and applicable compliance or migration test reports for the target market and use conditions. | Non-metal parts may have different temperature limits and regulatory requirements from the titanium body. |
| Quality management | Check whether manufacturing controls cover incoming materials, process inspections, nonconforming products, corrective actions, and lot identification. | Current ISO 9001 certificate, if claimed, verified with the issuing certification body; review its scope and validity rather than relying on a logo alone. | ISO 9001 concerns quality-management systems; it does not by itself certify a mug as food-contact compliant. |
| Batch traceability | Confirm that finished cartons or production records can be linked to a production date or lot, material certificates, inspection results, and relevant component batches. | Sample traceability records and a written procedure for handling complaints, returns, and corrective actions. | Traceability makes it easier to investigate quality issues and identify affected production. |