This 2.5" hard drive tray lets you add even more flexibility to how you manage your data storage with the SATSASBP425 and SATSASBP125 series backplanes. This spare drive tray can help you save time in a fast-paced work environment. It’s interchangeable with trays from the StarTech.com single-bay backplane (SATSASBP125) and the four-bay backplane (SATSASBP425), giving you an extra tray in addition to the trays you're already using, to create expandable storage or as part of a rotating back-up solution.