Polk Audio Monitor 30 AM3025-A 2-Way Bookshelf Speakers (Pair, Black) Pair of bookshelf 2-way speakers that delivers superior linearity, definition and sound imaging One 5.25-inch bi-laminate composite dynamic-balance driver is lightweight and stiff to produce extensive bass and midrange clarity with lower distortion. Equipped with one 1-inch silk polymer-composite dynamic-balance dome tweeter for crisp detailed high frequency response. All MDF construction and extensive cabinet bracing ensure resonance-free enclosures Built-in keyhole wall mounting brackets provides secure on-wall mounting