Thats what they call them. I also did some searching and I believe they are the same as Parker ballistic extreme. I would like to try to find the ballistic coefficient for the 250 & 275 grain. these are the one of the few bullets that seem to shoot good with a magnum charge.
here are the bullets
http://www.sportsmansguide.com/net/cb/cb.aspx?p=WX2&i=112287