| Navy | The Royal Navy |
| Type | Rescue Tug |
| Class | Assurance |
| Pennant | W 73 |
| Built by | Cochrane & Sons Shipbuilders Ltd. (Selby, U.K.) |
| Ordered | |
| Laid down | 11 Mar, 1940 |
| Launched | 6 Aug, 1940 |
| Commissioned | 19 Nov, 1940 |
| End service | |
| Loss position | |
| History | HMRT Prudent was renamed Cautious when she became a Dockyard Tug in 1947. Sold and renamed Rivtow Lion in 1964. She was finally sunk as a recreational dive site at Nanaimo, BC (Canada) on 6 February 2005. |