A point for model builders who are building a Gato Class boat "as built". A portion of the Gato Class (consisting of SS-214 to SS-221and SS-264) were designed with an access hatch in each engine room. The first five, SS-214 to SS-220 (I believe) actually had the hatch when commissioned. The forward engine room hatches all were removed and the hull opening replaced with a full hull plate in 1942.