Keystone filters for pipe

these stones allow absorbing excess moisture and enjoying a quality tobacco like an English or Scottish Davidoff blend... they are now indispensable to me!

Simple and effective when you cannot use filters

Yes, good

The box is nice, but small, and the weight of the container is not mentioned, which prevents any comparison with other similar products, a pity. (On a digital kitchen scale, I got 17g for the empty box and 20g of granules). As for the material, it seems as effective as that of other brands and prevents the 'gurgling' of moisture that can be heard when the bottom of the stove is soaked.
There the pellets are stone-colored, while at the competitor's they look more like crystals. As a result, could there be a difference in quality? Especially since in another description of this brand the word clay is mentioned!

A filtering supplement not to be neglected in addition to 9mm filters, but difficult to implement when packing a pipe during a walk. These granules are easily crushable.

TIP: this box, once empty, can hold 7 or 8 9mm filters instead of leaving them loose in your pipe bag.

Not too bulky, they are quite practical to use. As for effectiveness, a professional analysis would be needed to properly evaluate their absorption quality. I am suggesting an idea to the site managers so they can provide us with some useful information on this matter.