Each subwoofer size varies in power and frequency range. CASA-10B (10) - 300W RMS / 60Hz - 2.0kHz.CASA-12B (12) - 400W RMS / 55Hz - 2.0kHz. CASA-15B (15) - 500W RMS / 50Hz - 2.0kHz. The Citronic CASA Subwoofers are built to last. They are constructed of hard-wearing 15mm MDF and coasted in a textured paint finish, which should offer some resistance to unwanted spills - ideal in a bar scenario! The front grille is made from steel and not only adds to the solid construction but improves the sound quality too. There is a 35mm pole mount socket on top for connecting a PA speaker, and two handles for easy transportation. 15mm MDF cabinets with hard-wearing paint finish. 2 x side carry handles.