The serial-usb adapters that I used at my previous work, including the real one providing the proper 12V, where finger-size dongles with a serial port and a fle

The serial-usb adapters that I used at my previous work, including the real one providing the proper 12V, where finger-size dongles with a serial port and a flexible cable of similar length leading to USB-A connector. Essentially one one just attaches it to the serial cable and connect to the laptop as necessary making the dongle very unobtrusive serial cable extension.