These files were originally created by Darrin Hattaway, who did an excellent job of brining this vehicle into being for us. 
 
The SEAL Delivery Vehicle (SDV) is a manned submersible and a type of swimmer delivery vehicle used to deliver United States Navy SEALs and their equipment for special operations missions. It is also operated by the Royal Navy's Special Boat Service, which operates three SDVs.
 
The SDV, which has been in continuous service since 1983, is used primarily for covert or clandestine missions to denied access areas (either held by hostile forces or where military activity would draw notice and objection). It is generally deployed from the Dry Deck Shelter on a specially-modified attack or ballistic missile submarines, although it can also be launched from surface ships or land. 
 
As rendered in 1/35 scale, the finished dimensions are: 

Length: 191mm (7.5")
Beam: 58mm (2.3")

These files are easily scaled and can be used to create a smaller static display to go in conjunction with your scale RC submarine, or scaled up to allow you to create a fully RC version .