Made from Ethylene Vinyl Acetate (EVA) these disposable caps have different colors to help track samples. When using Chloroform or Acetone as a reference solution, please avoid direct contact between the sample and the disposable cap and long term storage over 2 hours. Scientists rely on the expertise and artistic skills of Wilmad-LabGlass engineers and glass specialists to manufacture NMR and EPR consumables and laboratory glassware of the highest quality. Used daily in academia, healthcare and chemical, petroleum and other industrial applications, Wilmad offers 7000+ items as part of their standard catalog as well as custom fabrication for individual glassware, glass repair services and OEM glass parts.