Dell OEM 3rd-Party Kits - Mfg Equivalent Part # 0R749K 450GB 15000 RPM SAS 3.5" Hot-Swap Hard Drive (these are 3.5 inch drives) Please check compatibility below: Kit contains one 450GB 15K SAS hard drive with one Dell SAS tray fully compatible with Dell PowerEdge 1900, 1950 III, 2900 III, 2950 III, 2970, 6850, 6950, 840, 860, R200, R300, R900, R905, SC1430, SC1435, SC440, T100, T105, T300 Servers. (additional Dell PE Servers and MD Arrays may apply)