Questor IV Support Obsolescence Notice


 After 23 years of support, Extrel CMS will discontinue field and technical remote support for the Questor IV, QGP, and MS250 process mass spectrometers as of March 31, 2018. Sales of these instruments ceased in 2005 with the introduction of the MAX300 platform, and a parts obsolescence letter was released in 2012.

We will continue to supply available replacement parts through December 31, 2018, although certain critical components for the Questor IV are no longer available due to technological obsolescence. Standard spares such as gaskets, filaments, oil, ceramic washers, etc. are still available but may not be after December 31, 2018.

Extrel’s mission is to provide our customers with innovative solutions that improve process and performance and lead to strong relationships. As part of this effort, we wish to provide you with several options for the replacement of your Questor IV. The MAX300-RTG™ Real-time Gas Analyzer and MAX100-BTU™ mass spectrometers are next generation replacements for the Questor IV platform, while the MAX300-LG™ Laboratory Gas Analyzer is ideally suited to replace the QGP and MS250.

For additional information on our product offerings, please visit our website ( or contact an Extrel CMS sales representative to decide which option is best suited for your needs.

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