Bowers & Wilkins XT4, serial 6913, 6914 Made in England 50w-150w power handling 86db, 8ohms 49 lb each - 44.8 x 6 x 7.9 Sleek, narrow, aluminum-encased three-way loudspeaker. The XT4 features Bowers & Wilkins' trademark Nautilus tube-loaded tweeter, a single five-inch woven Kevlar midrange driver mated to dual five-inch paper/Kevlar bass drivers.