To perform seated band rows, take the barbell out of the squat rack and place it on the outside of the backside of the rack. Take a band and lay it perpendicular to the barbell and put the barbell on top. Take the opposite ends and pull them together and run it through a normal close grip handle.
Now sit down in front of the squat rack (the opposite side of the where you put the barbell) and brace your feet up against the rack and perform a normal row with the close grip handle. Using a band for rows overloads the peak portion of the exercise and forces you to work much harder at getting the elbows and shoulder blades back and tight.
Seated Band Rows With Handle Back Exercise - Start Position
Seated Band Rows With Handle Back Exercise - Finish Position