@futzle @mike They're for two different kinds of connectors. RS-232 originally used a 25-pin DB25 connector, but many pins weren't used by most equipment, so by the 19990s, things had mostly settled on a simpler 9-pin DB9 connector.
It's "mini" relative to other DB25 adapters, not to any DB9 things -- which the other is.
The early null modem adapaters / gender changers / etc were all pretty large.
@ajft @ieure @futzle I'm 100% sure the "mini" explanation is correct, because yeah it's one of the smallest of its type for sure, but I wasn't wearing my glasses last night and it turns out the smaller one is a DE-15, for VGA. They probably weren't intended to be compared to each other like I did.
This is all from a pile of old Sun gear, for the record.
@ieure @mike Yes please?