Highly transparent. Ring mark individually calibrated to `In ́. Class A tolerances according to DIN EN ISO 1042. The PFA screw cap guards against contamination. Outstanding chemical resistance, can be used with strong oxidants, highly concentrated acids and alkalis, hydrocarbons, and ketones. With laser-engraved lot number and batch certificate. Thermal stress up to 121 °C (autoclaving) does not permanently exceed the tolerance limit. To preserve the ring mark do not clean at temperatures exceeding 60 °C. Also available with DAkkS calibration certificate or individual quality certificate.