SNT-SAC3141TL 4x3.5" HDDs in 3x5.25" Bays SAS/SATA Trayless Backplane Interface: SATA/SAS [SAS support: Primary channel] Drive Bays: 3 x 5.25 HDD Support: SATA-I, SATA-II & SAS Connectors: 4 x 7pin data connectors( primary) 3 x 4pin power connectors