Features. 2 SFF in the rear is only supported with a 24 SFF model or 12 LFF model. In the rear this leaves 1x 16 slot accessible. Rear drives require the addition of the High Performance Fan kit (867810-B21). Supports UFF SCM drives. Premium bay supporting SFF SAS/SATA; can be configured in Primary or Secondary riser location Slot 3 (Bottom slot) available in Primary or Secondary Riser location depending on configuration Bus width x 16 Connector width x 16 .