The design was a modified version of the Hajen-class with only one shaft with a larger 5-bladed propeller for improved underwater performance and reduced noise.

Draken, Vargen, Nordkaparen and Springaren were ordered from Kockums.

These boats were decommissioned 1988-90 and were succeeded by the Sjöormen-class and Näcken-class submarines.

One submarine, HSwMS Nordkaparen, was preserved and can today been seen at the Maritiman in Gothenburg.

This article about a specific military ship or boat of Sweden is a stub.