KF-23-IPF Series beige aluminum mobile rack w/ 3 fans (2 front & 1 rear). KF-21-IPF Series beige aluminum mobile rack w/ 1 rear fan. KF-22-IPF Series beige aluminum mobile rack w/ 2 fans (1 front & 1 rear). KF-21IPF-B Series black aluminum mobile rack w/ 1 rear fan.