SCSI: DB-25
Serial Ports: 2
Sound Output: stereo 8 bit.
ADB: 1
Ethernet:  none
Machine Gestalt ID: 98
PRAM Battery: 4.5V alkaline (Rayovac 840)

Minutiae:

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.

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.