From Apple-History.com

The first of a new breed, the idea behind the Duo 210 was to have a fully functional desktop computer (by way of the DuoDock) that also served as an excellent portable machine. The 210 ran on a 25 Mhz 68030 processor, had a 4-bit passive screen, 4-32 MB of memory, and an internal hard drive. Its most innovative feature was the 152 pin PDS that allowed it to dock with a docking station that might contain more RAM, a larger hard drive, or more VRAM for a color monitor. The 210 cost $2,250, and was discontinued in October 1993.

Codename: DBLite, BOB W (Best of Both Worlds), Cinnamon
CPU: Motorola MC68030
CPU Speed: 25 MHz
Bus Speed: 25 MHz
Data Path: 32 bit
ROM: 1 MB
RAM Type: unique
Minimum RAM Speed: 70 ns
Onboard RAM: 4 MB
RAM Slots: 1
Maximum RAM: 24 MB
Level 1 Cache: 0.5 kB
Screen: 9" supertwist grayscale LCD
Maximum Resolution: 4-bit 640x400
Slots: Modem, Dock (152-pin PDS)
Hard Disk: 80 MB
Serial: 1
Speaker(s): mono 8 bit
Microphone: mono 8 bit
Gestalt ID: 29
Power: 25 Watts
Weight: 4.2 lbs.
Dimensions: 1.4" H x 10.9" W x 8.5" D
Minimum OS: 7.1
Maximum OS: 7.6.1
Introduced: October 1992
Terminated: October 1993