The 17895 is a cable that was included with all TGA100A analyzers to connect the TGA electronics to the position 1 laser connector on the TGA100A dewar. The 17895 is still available as a replacement part. Some TGA100As had a laser in the dewar's position 2; for this cable, 17896 should be used. For a TGA200 running lead-salt lasers in positions 1 or 2, the 21954 or 22001 cable should be used, respectively. If a TGA100, TGA100A, or TGA200 has been upgraded to use a thermoelectrically cooled (TEC) laser, there is no need to use a dewar cable. The TEC laser module has its own cable attached.