Current reference materials produced and certified by Suisse TP are based on the former Alusuisse system why they are also listed here. We still have many older Alusuisse CRM in stock. The nomenclature is following the aluminium alloy designation. This means that CRMs with a designation of 6xx/yy have a composition that is suitable for 6000-alloys, while CRMs with 11x/yy are high purity CRMs. All our future CRM will follow this basic designation scheme. The number after the forward slash is the production lot. One lot has an identical certificate (with the exception of possible volatile elements that may require an individual S-certificate if so the element is marked with a *). When a new lot of a certain type of CRM is produced, element concentrations may slightly differ from the last lot and a new certification analysis done and a new certificate produced. If there is no recommendation for the sold out material, don't hesitate to contact us for an alternative product.