This item appears identical to a standard riverboat (20 foot long and 8 foot wide), and can be used as one.
Property: When underwater, the boat radiates a water breathing effect, protecting all passengers and crew as long as they touch it, however, the actual boat has an Armor Class of 15, and it has 80 hull points.
No rowers or sailors are required,if the command words are known. It will obey commands to start, stop, turn to port (left),turn to starboard (right), stop turning (while keeping the same speed), submerge, level off, and surface. The undersea boat can be fitted with grips so that the passengers can hold on to the sides and avoid drifting away.