SNAREWEIGHT Solid Brass #5 is the Gold Standard of Snare Drum Dampening.
The #5 adds mass to the head which helps to evenly smooth the lower-mid ringing frequencies that can't be reached with other methods of dampening, while keeping the tone of your shell intact. 
 
The unwanted ring of the high frequencies are shaped by the chosen insert in a snap by matching the insert with your favourite drum head.