Product review (5 stars): An excellent roduct at a bargain price
I followed a recommendation (someone's feedback/review left on the air humidifier  I was was interested in) and I have to confess, it is all of what was described. It is plenty of product, it is efficient and the quality / cost ratio is quite high. The product works and your filter's life will definitely be extended (to tell the truth, I have been using one filter for the whole season and it did not go bad yet - no stain or mold, some calcium none of the products similar to this one address but still OK).
I would highly recommend to buy it and abandon the product that advertiser themselves as "no mess, just drop in". Adding a cap of this to my water tank is not that cumbersome or an impossible task.