The J class was designed by the Royal Navy in response to reported German submarines with surface speeds over 18 knots (33 km/h; 21 mph).

[1] Armament consisted of six 18 inch (450 mm) torpedo tubes (four forward, one on each beam), plus a 4-inch deck gun.

[1] Originally, the gun was mounted on a breastwork fitted forward of the conning tower, but the breastwork was later extended to the bow and merged into the hull for streamlining, and the gun was relocated to a platform fitted to the front of the conning tower.

[1] J3 was built for the Royal Navy by HM Dockyard at Pembroke Dock in Wales and launched on 4 December 1915.

[2] After the war, the British Admiralty decided that the best way to protect the Pacific region was with a force of submarines and cruisers.