A knurled knob adjusts the amount of pressure used to press the snare wires against the frontplate. The rattle effect ranges between light and sensitive to very loud can be achieved through adjustment. The entire snare unit can even be turned off completely.
Click on the link below to hear an Mp3 of the Meinl Percussion Snare Cajon, American White Ash:
With its frontplate made from finest American White Ash (Fraxinus americana L.), this cajon lives up to the highest standards with regards to sound and quality.