SCSI: DB-25
Serial Ports: 2
Sound Output: stereo 8 bit.
ADB: 1
Ethernet: none
Machine Gestalt ID: 89
PRAM Battery: 3.6V lithium (Maxell ER3S, Radio Shack 23-026)


Minutiae:

Apple sometimes advertises this as a 50 MHz machine, since the clock speed is doubled inside the processor chip.  However, all I/O to the processor is done at 25 MHz. 

Requires symmetric memory.  This is only an issue when dealing with SIMMs which use 16Mb chips.  SIMMs built with symmetric chips are indicated by an "L" suffix on the part number.

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.