Subchasers of
SC-1 class were built in the US during World War I in large quantities.
Generally their armament consisted of a 3" boat gun, a Y-gun and a couple of small caliber machine-guns.
Some were armed differently. For example this SC-26 has a Hotchkiss 6-pounder and a
Davis recoilless gun.
After the war many of them were converted to merchant vessels and some returned to US Navy or US Coast Guard service at the outbreak of World War II.
Some were transferred to Coast Guard but most of them were struck due to expensive maintenance. This one however remained in service and was returned to US Navy after some modifications.