Initially both ships were commercial cargo ships of the C3 type taken over by the United States Navy during World War II and converted to attack cargo ships. The ships measured long between perpendiculars and overall with a beam of and a draft of . As attack cargo ships, they had a displacement of 11755LT. After their conversion to destroyer tenders, they had a light displacement of 8860LT and measured at full load. They were powered by steam generated from two Foster Wheeler boilers turning geared turbines creating 8500shp. This gave them a maximum speed of 18.4kn. The ships were armed with a single 5inches/38-caliber gun, four single-mounted /50 cal. guns and four guns. They had a complement of 857 officers and enlisted personnel.
| Hamul class construction data | ||||||
|---|---|---|---|---|---|---|
| Hull number | Name | Builder | Launched | Acquired by US Navy | Commissioned | Fate |
| AK-30/AD-20 | (ex-Doctor Lykes) | Federal Shipbuilding and Drydock Company, Kearny, New Jersey | 6 April 1940 | 5 June 1941 | 15 June 1941 | Broken up for scrap 1975 |
| AK-31/AD-21/AR-23 | (ex-Mormacpenn) | Ingalls Shipbuilding, Pascagoula, Mississippi | 21 December 1940 | 2 June 1941 | 15 June 1941 | Broken up for scrap 1977[1] |