Mont. Code Ann. § 61-3-344
61-3-344 Out-of-state USS Montana vehicles -- compliance with local state safety and emissions laws
61-3-344 . Out-of-state USS Montana vehicles -- compliance with local state safety and emissions laws. A vehicle displaying USS Montana specialty license plates and located for more than 1 month in the state that contains the home port of the USS Montana is subject to that state's laws regarding safety inspections and emissions testing.