We have three units. These special team unit have their own starters, backups and stars. We often talk about 25 or 26 on defense. I don't think that's quite right. We usually have 21 defensive players, some of which play special teams. 7 DL's, 7 LB's and 7 defensive backs. That's what we need to play defense. We also have 4-5 players whose primary role is special teams.