Intended as a shore bombardment vessel, M19's primary armament was a single 9.2 inch Mk VI gun removed from the Edgar-class cruiser HMS Edgar.

She was equipped with a four shaft Bolinder two-cylinder semi-diesel engine with 640 horsepower that allowed a top speed of eleven knots.

HMS M19 ordered in March, 1915, as part of the War Emergency Programme of ship construction.

She was laid down at the Sir Raylton Dixon & Co. Ltd shipyard at Govan in March 1915, launched on 4 May 1915, and completed in June 1915.

M19 was sold on 12 May 1920 for mercantile service as an oil tanker and renamed 'Delapan'.