10-in-1 Mac OS X Bootable USB for High Sierra, El Capitan, Catalina, Monterey, Lion, Mountain Lion, Mavericks, Mojave, Ventura, and Sonoma—128GB Fast USB 3.1 Dual Ports, Silver

I got a free Mac Pro 4,1 that needed an overhaul, it came with out an OS or optical drives. For my situation, this USB key was just the ticket. Follow the included instructions regarding the date & time for later Mac OS installations. It is a very simple command in the Terminal, and installation went quickly thereafter.

This worked great.I needed Catalina. Apple makes it so hard to download boot images -- to get an old boot image, you have to find another machine running the old OS. Chicken and egg problem.Got my old iMac 27" late 2012 up and running.

Tried several times but got message install disk corrupted. Changed date as instructed but got same message. Bad copy of osx install.

Followed paper directions, did have to do it a second time to be successful. Have High Sierra loaded and desktop is working great. Computer was directly plugged into router.We received a totally wiped older desktop. Originally tried several times going through start up and loading back Sierra OS through Apple and Safari. Kept getting error messages with ever attempted path.

High quality drive and an incredibly useful tool for old farts such as myself who love to reinstall older, and in some cases obsolete operating systems on older hardware which is still healthy! Not all Macs can do internet recovery, and I helped one friend recently whose ISP was blocking access to Apple Servers. Love it! Highly recommended.

I try to get it to work but its difference i do not understand it

i dont know why anyone would complain, simple to use, installed fast, A+++++ mac os installer

Needed to re-install MacOS High Sierra on a MacBook Pro from 2010, and tried for a whole week with no success; bought this thumb drive and it installed on the first try