Because sensor-heads are field-swappable, and because all X Series instruments share the same architecture, you can place whichever sensors you need on your instrument model of choice.  Total flexibility - of instrument model, of sensor type, and of sensor range - ensures that the right instrument is always available.

Within the X•Series family, there are two real-time instruments, the Micro•X and the Smart•X.  The Micro•X - the instrument in the farthest background - is a single sensor real-time instrument often used in transducer mount or sea chest applications.  2nd from back, the Smart•X is a real-time multi sensor probe designed for AUV, ROV, and other integration work. 

There are also two loggers in the X Series family.   The Minos•X - 2nd from front - is a small vertical profiler, ideal for work in confined spaces like small launches or boat.  At front, the Plus•X is a full-sized multi-parameter instrument ideal for profiling or in-situ studies.  All four of these these instruments are compatible with the four Xchange^TM field-swappable sensor-heads: SV•Xchange^TM, C•Xchange^TM, P•Xchange^TM, and T•Xchange^TM.

But the X•Series lets you do much more than just adjust the sensor load of one instrument.  All X•Series instruments share a common architecture.  This means that any Xchange^TM sensor-head can be attached to any instrument, regardless of size or type: real-time probe, vertical profiler, or in-situ logger.    What does this mean?  To build upon the example above, one of the sensor-heads attached to the Smart•X could be redeployed to a Plus•X to log a vertical profile.