IBM UltraBase X4
The IBM UltraBase X4 is a portable dock for the X40 and X41 ThinkPads providing extra ports as well as a bay for an optical drive and a set of stereo speakers. Containing a full featured UltraBay Plus slot, it provides flexibility in drive choice as well as the option of a secondary battery for extended working time on the road. The UltraBase X4 doesn't provide a second docking port as the original UltraBase did, hence you can't dock the UltraBase to any of the other docking solutions.
- USB (three ports)
- Serial (9 pin)
- Parallel (25 pin)
- PS2 Keyboard/Mouse (shared port)
- Ultrabay Plus
- Stereo speakers
- Kensington security hole
Pros & Cons
- Positives: Expansion capability, portable
- Negatives: makes the ThinkPad quite thick, no extra docking port
- Compatibility: X40, X41
- Warranty: Three Years
The UltraBay Slim slot in this dock is a full featured one and supports hot swapping with all UltraBay Slim drives. You can also feed it with the UltraBay Slim battery pack to extend the overall battery life time.