Why won't Apple's original 1TB SSD fit in my JDM 855/825 enclosure? Category : Compatibility To allow for higher capacity, Apple has widened the PCB for its 1TB SSDs, so that compared to Apple's other SSDs, the 1TB SSD comes larger in size. This is why the original 1TB SSD from Apple won't fit in the JetDrive 855/825 enclosure. Is the answer helpful? Related Why does my Mac computer take longer to boot after I upgraded it with JetDrive SSD? Error Message shows not enough disk space during using Boot Camp Differences between JetDrive 825 and JetDrive 820. Technical Support If the answer can't help you, you can contact the Tech Support Department Get Started