PCSG DISK+

PCSG DISK+ is a file transfer client that connects over serial to a matching server running on some other host computer, similar to TANDY RemoteDisk.

It included a dialer and supported using the modem to dial the remote machine over the phone, not just a local direct serial connection.

Option rom images:
PCSG Disk+ 2.0 for Model 100
PCSG Disk+ 3.1 for Model 100