Mac OS X Universal Binary Driver v1.6.4 (PKG file format)

For Mac OS Catalina (version 10.15) - see NOTE below.
For Mac OS Mojave (version 10.14)
For Mac OS High Sierra (version 10.13)
For Mac OS X Sierra (version 10.12)
For Mac OS X El Capitan (version 10.11)
For Mac OS X Yosemite (version 10.10)
For Mac OS X Mavericks (version 10.9)
For PL2303 HXD/EA/RA/SA/TA/TB chip versions
For Prolific USB VID_067B&PID_2303 Only
 

Third-Party Compatible Drivers:

PL2303 Serial-USB on OSX Lion
Mac OS X Prolific PL2303 driver project

             -2303G_driver for Mac 11.X

             -2303G_driver for Mac 10.X

             -2303HXD _driver for Mac 10.X

For Mac OS Catalina (version 10.15) - see NOTE below.
For Mac OS Mojave (version 10.14)
For Mac OS High Sierra (version 10.13)
For Mac OS X Sierra (version 10.12)
For Mac OS X El Capitan (version 10.11)
For Mac OS X Yosemite (version 10.10)
For Mac OS X Mavericks (version 10.9)
For PL2303 H/HX/HXD/EA/RA/SA/TA/TB chip versions
For Prolific USB VID_067B&PID_2303 Only
For PL2303GC, GS, GT, GL, GE , GD, GR chip versions
Includes Driver Installation Manual
NOTE: Mac OS High Sierra 10.13 introduces a new feature that requires user approval before loading new third-party kernel extensions. Go to System Preferences - Security & Privacy and click Allow. 

https://developer.apple.com/library/content/technotes/tn2459/_index.html