Handspring Visor Deluxe, a PDA from 2000 running the Palm OS platform. Don't mind the tablecloth. XD
I bought the PDA itself for $1 at Goodwill, while the Serial Docking Cradle was purchased for $15 on Amazon. It does indeed function with a USB-to-Serial adapter; in fact, that's how I get data from the Visor to Windows 98 in Oracle VirtualBox.
The tip of the stylus pen unscrews to reveal a plastic pin that you can use to reset the Visor, while the back end unscrews to reveal a small Phillips screwdriver.
Picture Added July 5, 2017, 12:00:26 PM (-07:00)
Added by Seiji J. Konokama