From the FASA Star Trek ROMULAN SHIP RECOGNITION MANUAL, circa 1985
P-12 (Comilius) Class II Cutter
Known Sphere Of Operation: Federation and Triangle borders
Data Reliability: B
Major Data Source: Klingon version in Star Fleet possession; Klingon sector intelligence
These Klingon vessels were traded to the Romulans beginning Stardate 2/1409, largely because of pressure on the Klingons to replace the structurally-weak N-8 (Klingon K-3) vessels.  The P-12s also were altered to mount RomuIan engines, weapons systems, and shields, but the modifications actually made the ships more structurally sound, probably because of the added support required for the tandem warp engines.
        As of this date, only one type is believed to be in service.  It obviously has proven effective in its gunboat/systems patrol role, and it is being used along Federation borders and those of the Triangle.  Of the 220 acquired in the exchange, about 200 are in active service.  Six have been been seen in the Triangle operating in the civil sector.
        The class is said to have been named for the famous Praetor Comilius, who, after suffering several serious defeats at the hands of his enemies, withdrew to his capital city to hold out for six years against the massive armies that each had assembled.  He negotiated an alliance with one of his adversaries and broke the siege, later conquered his remaining enemies, and brought peace to his people that lasted a century.