75 Pa.C.S. § 6144: Vehicle registration and licensing.

An agreement or arrangement entered into, or a declaration issued, under this subchapter may contain provisions authorizing the registration or licensing in another jurisdiction of vehicles located in or operated from a base in the other jurisdiction which vehicles otherwise would be required to be registered or licensed in this Commonwealth. In such event, the exemptions, benefits and privileges extended by the agreement or declaration shall apply to the vehicles when properly licensed or registered in the base jurisdiction.