Reason+ is a service (for 1 year). That means when you subscribe you get:

Inspiring sound packs delivered weekly. Organized around themes like Neo-Soul, Beach Party, Cinetronica, Grime 'n' Garage and uses like Essential Guitar Effects, Trap Drums, Liquid Breaks, Pop Chord Progressions, Sound Packs will jump start your music making and lead you in new directions. People are amazed how much these unlock Reason and its devices, guiding you to create your sound. We’re starting out with a bunch of great packs of patches and intend on releasing ~10 packs a week.

All Reason Studios devices and any new ones we develop. Today that means 75 instruments, effects, and MIDI players, including the recently released Friktion and Pattern Mutator.

The latest up-to-date version of Reason software, both standalone DAW and Reason Rack Plugin for VST/AU/ AAX. No matter where or how you work, we got your back. All the new stuff we make you get access to immediately.

A new Reason+ companion application that manages your Reason life and lets you discover and install these new packs, Rack Extensions and Reason, too.

!!! For this software you will receive two codes for activation, an Unlock Code and the Serial Number. In the confirmation e-mail which you will receive from us after purchase, the two codes are separated by the symbol “/” (slash). Example: XXXXXXXXX-XXXXXXXXXXXX / YYYY-YYYY-YYYY-YYYYY

The user must visit this webpage to register the obtained code.
https://www.reasonstudios.com/plus/registration?subchannel=muziker
The page guides the user to register a new Reason account or login to an existing account.