he 2.4 GHz Radio for the Controller and Robot Brain
Update your firmware! The 2.4 GHz Radio requires Robot Brain firmware v1.10 or newer and Controller firmware v1.02 or newer. See www.vexiq.com/firmware for more information.
If you are purchasing this radio because your radios do not work make sure you read this https://kiwibots.co.nz/kiwiblog/entry/vex-iq-radio-issues-not-working first.
Do not remove radios https://kiwibots.co.nz/kiwiblog/entry/vex-iq-do-not-remove-rf-modules-for-any-reason