The Protector was the pioneer Submarine Torpedo Boat of the Lake level-keel type, and was built by the Lake Torpedo Boat Company in Bridgeport in 1901-1902, - launched at Bridgeport Conn. on November 1, 1902. The Protector was designed for coastal defense and there was considerable controversy between the Lake & Holland submarines. Many officials in favor of the Lake-type, even-keel submarine verses the Holland diving type. However, the military were already familiar with the Holland subs and stayed with that type.
Both Japan and Russia were keenly interested in the Protector, and it was sold to Russia and shipped to St. Petersburg, during the Russian-Japanese war. From St. Petersburg she was shipped to Vladivostok, 6,000 miles across Siberia, special cars being built for her transport. Bridges had to be strengthened and in some cases special provision made to pass her through tunnels. She was very successful, and Russia ordered five additional boats of this type which were manufactured by the Newport News Shipbuilding and transported abroad.
The success of the Protector, renamed “Osetr” in Russia, led to additional contracts for the Lake Company to build additional cruiser-type submarines, all forming Russia's first submarine force fleet of practical military submarines.
The significant achievement of the Protector submarine is that it established a new worldwide precedent for submarine design of the even-keel type. Unfortunately, the United States did not properly acknowledge this fact until foreign governments achieved an obvious measure of success with the Lake submarine.