Really good way to tame your bass drum. Sound is no more resonating, only a good thump remains. I would have appreciated a little more reso...
Install it on the bottom of your bass drum, it should touch and slightly push both heads. Beware to choose the right size !
I don't have one yet, but it creates also a flat surface if you want to have an inside mic, good thinking. The foam looks durable, and the little pressure is enough for it to not move around, no need for adhesive (even if they are provided in the package)
All in all, a good and modern product to use instead of an old pillow :)