Meinl PSUBCAJ6B Pickup Vertical Subwoofer Cajon (Baltic)The MEINL Pickup Vertical Subwoofer Cajon with Baltic birch playing surface features forward projecting sound ports in place of the traditional rearfacing style and an internal reflex channel that helps develop the sound. When amplification is needed, inside the cajon is a Piezo pickup with tone and volume control on the outside. A quarter inch cable port allows you to send your signal through any amp or PA system. Specifications Vertical forward