This unit replaces the primary factory internal hard drive. No hard drive carrier/caddy included, you can use the existing carrier/caddy on your original factory drive. Possibly the best upgrade available for your notebook/laptop. Need more storage or a backup solution. Purchase a 2nd Hard Drive Adapter to run in your Ultra bay slot for supported models Features (Unique to IBM/Hitachi Travel star Hard Drives): > Enhanced Adaptive Battery Life Extender 3.0 for maximized battery life > Fluid Dynamic Bearing Spindle Motor for lower acoustics and increased non-operating shock tolerance > Advanced noise reduction using a Voice Coil Motor (VCM) Damper > S.M.A.R.T. compliant detection system that gives advanced warning of possible drive inconsistencies >Stiffness-reinforced base casting construction offers enhanced stability and greater vibration/shock resistance > Antihero magnetically coupled (AFC) "pixie dust" media >Specula Layer giant magneto resistive (GMR) heads > Ramp Head Load/Unload technology > Partial Response Maximum Likelihood (PRML) read channel >Adaptive Formatting > The 7200-RPM performance will provide end-users with noticeable improvements in start-up and data access time and in running data-rich applications such as graphics, spreadsheets or audio and video files. Higher RPM, increased data rate, advanced cache management software, larger cache size, and a faster hard disk drive microprocessor unit from the previous generation 4200rpm models.