This single is available in this CD collection: Singles 7: 1970-1972. Also available in this MP3 collection: The Singles Vol. 7: 1970-1972.
What can one say about this monster of classic funk? JB and Bobby Byrd lay it down as hard and thick as it gets with groove as the band burns down the house.
Tons of great info on this song at Wikipedia.
Bonus live must see version!