Focal B.A.M XL Sound Insulation KitB. A. M XL Sound insulation kit Effectively insulate your car roof or doors with this acoustic insulation kit containing two 50 x 200 cm sheets. With B. A. M., made from technical materials (Butyl. Aluminum. Foam), you can increase the bass level in your vehicle while isolating it from external noise. Less noise, more music! THREE MATERIALS, THREE FUNCTIONS The B. A. M. consists of a honeycombed damping material that attenuates the rear wave of the