His testimony regarding what he witnessed is quite extraordinary, and the technology he encountered while trying to understand its basic functionality was completely out of this world. Evidently, the government was unable to explain how the technology worked when Bob was at the secret base.
In these interviews, he discusses working at Area 51's S-4 facility and seeing materials that did not exist at that time. In fact, Element 115, which created anti-gravity properties, was first synthesized in 2003 by joint US/Russian scientists, as described.