Vintage National 16 Ohm  Triaxial Speakers. These speakers feature 3 completely independent speakers with 3 separate voice coils in a single 10″ compact unit. T Specifications: Frequency Response: 20 to 20,000 cps (30-18,000 cps +/- 3 db) Revolutionary Conical “Stiffener” Eccentric Baffle Mounting of Midrange & Tweeter Eliminates Interaction Between Speaker Cones Built-in Crossover Network and Brilliance Control Extremely Efficient High Excursion Woofer Free Air Resonance 35-55 cps Impedance of 16 ohms Power Rating: 20 watts Average Program Material Overall Diameter of 10″ Overall Depth of 7″