sentences:  In the West, the class was much more widely known for its nickname, "Stalinets", coined with reference to earlier boats of the "Leninets" type, but it was never featured in any official documents.The E-1 boat was eventually sold to Turkey in 1935, and was a prototype for German's own boats of Type I.This design was later improved to become the famous Type VII and Type IX U-boats of the "Kriegsmarine".