Turtle Cajon

This is my first attempt to make a small cajon. It has a compartment for ball bearings (to act partially as a shaker). If the ball bearings are magnetic, you can add a magnet to "turn off" the shaker. I am making a second tapa with a snare under it. The bottom will still be a tom while the snare is above. And I might add a jingle that can be mechanically turned on and off - someone can mod that for me?