shipstamps.co.uk

These ships were enlarged versions of the Aréthuse class submarines. Eleven were used by France. Boats of this design were sold to several other countries: Pakistan (3), Portugal (4), South Africa (3) and Spain (4). However, two (Euridice 1970 and Minerve 1968) sank accidentally and brought sales to an end. The cause was eventually considered to have been a faulty snorkel design. The submarines were scrapped in the 1990s and Portugal sold one of its boats to Pakistan. PNS Hangor sank the Indian frigate INS Kuukri during the 1971 Indo-Pakistani war. Pakistan has now retired the submarine and is replacing it with the French Agosta and Agosta-90B, for which France has given Pakistan transfer of technology & licence to export to other friendly countries.
Wikipedia.
Pakistan SG763