The four 240-foot cutters were conceived as the first true "multi-mission" Coast Guard cutters, equipped for police work in territorial waters, ice patrol, search and rescue, derelict destruction, and towing. Each ship had a remarkably heavy armament of two 5-inch guns, with a provision for the wartime installation of a third, and a 3-inch anti-aircraft gun. A turbo-electric drive system gave the cutters a top speed of sixteen knots, which seemed plenty for the Coast Guard's peacetime missions. The four ships were built by the Union Construction Company of Oakland, California.
Here's Modoc in 1942 while in Greenland Patrol, wearing Measure 16 camouflage. The armament complemented with a second 3"/50 gun, machine-guns and depth charges.
Here's Tampa in 1943. Pretty much the same layout, different camo: