The tube sealing equipment (TSE) is a compact, manually operated vacuum line equipped with two 9 mm Ultra-Torr® ports for sealing of combustion tubes, two 4 mm ports for sealing of quartz and glass tubes and one ½” Ultra-Torr® port with a bellows tube cracker for 9 mm sample tubes. The line also includes two calibrated volumes (corresponding to ca. 700 and 2000 µg carbon as CO2 at 1 bar), two pressure sensors (0 – 1000 mbar) with digital readouts and a Peltier cooler for water removal. TSE is best suited for re-freezing of samples (1 – 2000 µg C) for the gas interface system (GIS) and for sealing of samples for tube combustions. Liquid nitrogen is used for transferring and freezing of CO2.