Each CD Plus package is good for 50 CDs and mainly consists of 50 small blue rings, an orange centering guide and of course instructions on how to install the rings onto your CD. The blue rings mount around the center hole within your CD to add a bit more mass, but more to the point, to help add stability and better mechanical gripping of the CD's center to the spindle/motor. This, Compact Dynamics claims, reduces CD vibration during playback. It is actually quite easy to mount a blue ring to a CD, though keep in mind this is a permanent arrangement. Though you can remove the ring if you do not like the results, the ring really cannot be reused again.
To mount the blue ring to the CD, you simply place the compact disc, label side down, centrally on top of the supplied micro-foam disc. Insert the small end of the orange centering guide into the hole of the compact disc and leave the guide in place for centering the blue ring. Then you remove from CD Plus's blue ring one half of the full circle's backing paper. Then place the blue ring (paper side down) over the CD's shiny side centered on the orange centering guide. Preventing the centering guide and blue ring from moving, remove the rest of the protective backing paper and insure the entire ring is secured to the CD by pressing down on it.
"So what did I hear? I consistently heard a bit more smoothing of the music within the CD yet also a tad more resolution. It was as though a level of haziness was removed from the CD. In fact, I had a few really old CDs that simply skipped quite a bit. I keep these around to test how a disc transport can read less than perfect software. The rings seemed to help, but not fully solve the skipping problems. Obviously something good was happening here and not some voodoo magic."
– Steven R. Rochlin, Enjoythemusic.com