Only 3 months old and in excellent working condition (like new) Originally paid $329 each ($658 for pair) The S55 is made with high-quality materials for natural, low-distortion sound. Its cabinet houses a 1" high-resolution Terylene dome tweeter for clear, detailed highs and realistic reproduction of instruments and vocals. Two highly efficient 6-1/2" Dynamic Balance® woofers are made of lightweight yet durable mica-reinforced polypropylene. Non-resonant MDF (Medium Density Fiberboard) construction and an anti-diffraction magnetic grille provide an acoustically inert structure for reduced sonic interference. Polk's exclusive Power Port technology adds bass impact.