Product review (5 stars): Works well and Saves time.
I paid $4.00 for this 12 pack Mineral Absorption Pads.  That is less than about 33 cent each.  I used the mineral pad which came with my humidifier machine and used white vinegar lengthen the its use.  The idea is to use vinegar to dissolve the minerals deposited on the pad and to regenerate it.  The original pad eventually broke down after many usages.  In my experience, the pad becomes less effective after consecutive vinegar regeneration method.

I were out of a pad and minerals deposited very quickly on the heating element of my humidifier.  I had to soak the heating element in vinegar every week for hours to loosen the mineral.  When I waited longer than a week, the deposited minerals became extremely tough to remove.  There were a lot of scrubbing.  These became very time consuming and labor intensive.  When the new pad came, I can see a huge difference.  I had been using the very first pad from the box.  It has been 2-3 weeks and there is minimal deposit on the heating element, though some.  33 cents for saving me hours of scrubbing my machine -- what an excellent time saver.

The pad came bigger than my heating element, so I had to cut it to fit.  No big deal.  10 seconds of work.  With a 12 piece mineral pads, I expect they will last me through the next two winters.