Swedish Delfinen-class submarine

	HSwMS Springaren in 1935
Class overview
Name	Delfinen class
Builders	Kockums
Operators	Swedish Navy
Preceded by	HSwMS Valen
Succeeded by	Neptun class
In service	1936–1953
Completed	3
Scrapped	3
General characteristics
Type	Mine-laying submarine
Displacement	Surfaced: 540 tons; Submerged: 720 tons;
Length	63.09 m (207 ft 0 in)
Beam	6.40 m (21 ft 0 in)
Draft	3.40 m (11 ft 2 in)
Installed power	Surfaced: 1,200 bhp (890 kW); Submerged: 800 shp (600 kW);
Propulsion	2 × MAN diesel engines; 2 × electric motors; 2 shafts;
Speed	Surfaced: 15 knots (28 km/h; 17 mph); Submerged: 9 knots (17 km/h; 10 mph);
Complement	34
Armament	4 × 533 mm (21.0 in) torpedo tubes; 1 × 57 mm (2.2 in) deck gun; 1 × 25 mm (0.98 in) anti-aircraft gun; 20 × naval mines;

The Delfinen class was a trio of minelaying submarines operated by the Swedish Navy between 1936 and 1953. The boats were the first class of minelaying submarines in the Navy and were later used as the basis for further submarines developed immediately before and during World War II. They had an uneventful service history, and were all retired in 1953.