| Monitor | Comm | LOA (ft) | Beam (ft) | Std. Disp. (tons) | Full Load Disp. (tons) | Shafts | Armor | Speed kts | Guns |
| Roberts | Oct 1941 | 373.33 | 89.75 | 7973 | 9150 | 2 | 5 | 12.5 | 2-15" (1x2), 8-4" (4x2) |
| Abercrombie | May 1943 | (373' 4") | (89' 9") | Abercrombie 8536 | Abercrombie 9717 | ||||
| LOA (inches) | Beam (inches) | Std. Disp. (lbs) | Full Load (lbs) | Pump | Armor | Speed 100' | Guns | ||
| 46.67 | 11.22 | 20.2 | 23.2 | 3/4 | 1/16" | 91.1 | 2-1/4" (1x2), 8-1/8" (4x2) | ||
| Abercrombie 21.6 | Abercrombie 24.6 |