This is a P-3B Heavy Weight. The Heavy Weight version had a strengthened structure and was able to carry a heavier payload. It was delivered to the USN on 20 November 1967 and had been operational with a range of units until 1994. It went to AMARG in March 1994 and in January 2003 was selected to be sold to Pakistan. The aircraft, however, was not taken up by Pakistan and in 2017, when this photo was taken, it was still awaiting its fate.