Conversation so far:
What did the stooges collection consist of?
The set contains shorts from the first three years the Stooges worked at Columbia Pictures.
What were these shorts called?
The Three Stooges Collection, Volume One: 1934-1936.
Was there a volume two of three stooges?
release.
Volume Two: 1937-1939.
How many volumes were there?
A 20-disc DVD boxed set entitled The Three Stooges: The Ultimate Collection, including all 190 shorts from volumes 1-8 and additional bonus material, was released on June 5, 2012.

Question: What additional bonus material was included?
Self-contained rewrite: What additional The Three Stooges bonus material was included?