The RC 24 and RC 48 REVERB CLASSICS plug-ins are part of the KOMPLETE 9 ULTIMATE bundle. However, the REVERB CLASSICS were not included in early KOMPLETE 9 ULTIMATE installers. In this case, you won't find them among your NI plug-ins and you have to install them separately.
You will find the download links for the RC 24 and RC 48 installers here on our website. Once downloaded, simply run the installer and these will be ready to use. There is no additional activation needed, since these products are part of the KOMPLETE 9 ULTIMATE bundle.