A flow-through sample container, or flow cell, according to the present invention resides with the channel of magnetic resonance probe without being fixed thereto. The flow cell is removable from the spectrometer while leaving the probe in place, allowing easy cleaning of the probe channel and replacement of the flow cell. An insertion tool that houses the flow cell may be used to safely introduce it to the probe. Input and output capillaries serve as fluid pathways for fluid samples entering and leaving the flow cell, respectively. These capillaries may be connected to the flow cell with a manually operable connector, allowing easy disconnection of the flow cell from the input and output conduit. The capillaries enter through different ends of the spectrometer bore, so that the fluid samples flow enter one end of the spectrometer and exit through the other.