Hi lexlee,
the difference are the licenses and apps installed on the ctrlX CORE. in R911...037: only the operating system is onboard. in R911...308: EtherCAT Master and CustomerApp (= DataLayer NRT) Apps and licenses are onboard.
To find out such configurations difference, you can put the material number in the search field of the configurator and it will displayed which licenses&apps are installed:
configurator
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