While the indoors version is made with raw carbon steel with matte powder coating, this Outdoors version is made with galvanized steel with bright outdoors powder coating. Hence, if the pull up bar will be installed unsheltered outdoors, you should strongly consider this version.
No screws, no drilling needed.
Very simple to set up and use.
Comes with premium extended foam handles to improve grip.
Note that there will be screws given in the package and it is optional to use them.