Frank Chadwick's 'bathtub' warships

I would really love some more information about Frank Chadwick's 'bathtub' warships, but all I can find is the section in BARBAROSSA 25 that deals with naval forces. It states the following:

'Both sides have limited naval capacity during the time represented by Barbarossa/25. The Soviets have destroyers and torpedo boats, while the Germans have an inherent naval transport lift capability. The following rules detail the abilities and limitations of the naval forces.

Soviet Naval Forces

The Soviets have four destroyers, as well as five torpedo boats. The characteristics of the Soviet destroyers (DD) and the Soviet torpedo boats (TB) are noted in the table which is located in the next column.

Armament is the vessel's main weapon and may be used for shore bombardment. In both cases it is equivalent to a single gun stand (battery). The destroyers are armed with 122mm guns, not howitzers. The AA armament can be used to attack any plane which is attacking the ship or attacking any other target in a port which the ship is in. Flotation is the number of hits the vessel can take before sinking. Lift is the number of personnel stands the vessel can transport. (in this case, the size of the stand being transported is irrelevant.)

Items other than personnel stands may be transported at the following rates:'

One is left with the impression that Frank Chadwick's 'bathtub' warships were probably quite basic to look at, and that the destroyers were probably two-thirds to a half the size of the destroyers.