Supported System Software: 7.1.2P, 7.5, 7.5.1, 7.5.3
SCSI: DB-25
Serial Ports: 2
Sound Output: stereo 8 bit.
ADB: 1
Ethernet: use Newer Technology 7ET-L10 or 7ET-C10
Machine Gestalt ID: 98

Minutiae:

SIMMs are installed in groups of one.  The second SIMM socket can only accept a 1,4, or 16Meg SIMM. 

Apple sometimes advertises this as a 66 MHz machine, since the clock speed is doubled inside the processor chip.  However, all I/O to the processor is done at 33 MHz. 

Sound output is 16-bit stereo for CD playthrough.  Sound output is 8-bit for Macintosh generated sounds.  Front headphone jack is 16-bit stereo.

Original enabler: 405

Serial Port with the phone icon supports synchronous modems, with handshaking on both output and input supported.

Has 1MB ROM and a 1.44MB SuperDrive.