A hard disk drive assembly which is small enough to meet the PCMCIA type I or type II formats and which has an outer layer of elastomer material which seals the assembly and absorbs external shock or vibrational loads applied to the drive unit. The disk drive unit includes a housing which encapsulates a magnetic disk and accompanying hardware required to read and write information onto the disk. The housing typically contains a cover plate and a base plate which are attached to a frame. Connected to the outer edges of the plates and frame is a layer of elastomer material. The elastomer seals the covers to the frame and absorbs external loads that are applied to the edges of the housing.