yes you need it, the bracket that states LGA 2011.
there is a difference in the measurements (CPU cooler and push/pins) of the LGA 1155/1156 will not fit.
now if the box says LGA 2011 then you have the latest revision and as stated below 'djdecibel'
then your set with just the retail package.
I just checked link and it says on the box and listing LGA 2011, so by that right there, it comes with..