It is an air chamber, which is a full goatskin bag, and functions as a wind instrument. One end has two bamboo pipes, with reeds and finger holes, inside the container. One pipe is for note and the other for drone. The other end is attached to a bamboo, through which air is filled. The inflated goatskin expels as air fills and makes the reeds to vibrate. Thus, music is produced. The instrument is played in Rajasthan.

Other than a musical instrument, Mashak functions as a water container and an air container. When sealed and filled with air one can use Mashak to cross rivers.