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@@ -84,8 +84,14 @@ It's really important to control the temperature and humidity of the room becaus
 
 ## Examples of ICP Mass Spectrometers
 
+The mass-analyzer used in the instrumental setup defines the type of the ICP-MS. These set-ups consist of magnetic sector, quadrupole, TOF, and tandem mass spectometers (two or more mass analyzers).  
+
 ### Quads
 
+In most of the set-ups ions are guided to a [collision/reaction cell](@sec-design-crc) that is pressurized with reactive or non-reactive gasses to reduce the spectral interferences between unwanted ions (e.g., ArO^+^+ and ^56^Fe). Many ions and reaction products emerge from cell and passes through [quads](@sec-analzer-quadrupoles).  
+
+Similar set-ups are used by different manufactures [Thermo](@https://www.thermofisher.com/us/en/home/industrial/mass-spectrometry/inductively-coupled-plasma-mass-spectrometry-icp-ms/quadrupole-icp-ms-systems.html) and [aglient](@https://www.agilent.com/en/product/atomic-spectroscopy/inductively-coupled-plasma-mass-spectrometry-icp-ms/what-is-icp-ms-icp-ms-faqs) in which the ion paths are respectively perpendicular and horizontal.  
+
 ### TOFs
 
 ### Magnetic sectors