When I use the LRU for Regulatory Testing on the 40 series radio, the Regulatory Domain selection remains grayed out.

The 40 series loads a Regulatory firmware to allow hardware testing of max Tx Power when the Laird Regulatory Utility (LRU) is used. Tx Power for each channel under each Regulatory Domain supported (ETSI, FCC, KCC, TELEC, WW) is tested with an in-line WLAN monitor for a client connected to an AP at different data rates to ensure compliance.