The Shark is a "gated drum dampener". It attaches to the drum head, next to the rim of the drum. With its adhesive back, it stays in place.
When you hit the drum, the biggest part of the damper tilts up. This allows the head to - quite briefly - vibrate freely, only to be dampened again by the damper when it falls down.
The product is delivered in a small box, and a small self-adhesive strip is also included, which is used for coated drum heads.