1pcs Mini Null Modem Db9 Female Male Plug Adapter Gender Changer Cross Female To Female/male To Male Rs232 Serial Connector - Connectors - AliExpress
I have a great idea! I'll buy an RS-232 to USB adapter and a separate null-modem cable! Much more versatile. No way I'll lose one of them... : r/homelab
RS232 null modem | Null modem adapter
PSG08434 - Pro Signal - 9 Pin Mini Null Modem Adaptor Male-Female
DB9 Male to DB9 Female Low Profile Null Modem Adapter - Sealevel
Null Modem Adapter Serial DB9 Male to Male | Computer Cable Store