Brand NEW! Including 90 Days USA Factory Warranty. The Dayton Audio Designer Series passive radiators are excellent general-purpose passives suitable for replacement or for new construction. Built to be a perfect match for the Designer Series drivers, these passive radiators feature the same steel frame, rubber surround, and treated paper cone making them visually identical. Key Features ? Perfect match for Dayton Audio's paper cone Designer Series drivers ? Allows tuning small enclosures lower than using conventional ports ? Rear mounted screw allows easy mass adjustment for custom tuning ? Cosmetic frame edge looks great even when surface mounted The Dayton Audio Designer Series passive radiators are excellent general-purpose passives suitable for replacement or for new construction. A built-in mass disc offers a good starting point for most designs, and a convenient M5 threaded hole (screw included) allows different types of weights to be added if desired. Cosmetically and mechanically, these passives match Dayton Audio's Designer Series drives, with a poly coated paper cone and medium-roll rubber surround for clean excursion and long life. The possibilities with these passives are endless, from floor standing two-ways to portable battery powered speaker systems. Specifications: ? Fs: 42.4 Hz ? Vas: 0.124 cu. ft. ? Qms: 5.9 ? Cms: 2.55 mm/N ? Rms: 0.3 kg/s ? Mms: 5.5 g ? Sd: 31.2 sq. cm. ? Xmax: 4 mm ? Dimensions: Overall diameter: 3.63", Cutout diameter: 2.76", Depth: 0.86". Note: Adding mass to the passive radiator will decrease Fs and increase Qms. Tip: As a general rule, the passive radiator(s) should have at least double the displacement of air (Vd) as the active woofer(s)/subwoofer(s) in the system. To calculate Vd: Sd x Xmax = Vd Product Specifications Nominal Diameter 3" Bolt Circle Diameter 3.27 Moving Mass Of Diaphragm (Mmd) 5.5 Thiele-Small Parameters Resonant Frequency (Fs) 42.4Hz Mechanical Q (Qms) 5.9 Compliance Equivalent Volume (Vas) 0.124ft Mechanical Compliance of Suspension (Cms) 2.55mm/N Maximum Linear Excursion (Xmax) 4mm Surface Area of Cone (Sd) 31.2cm Materials of Construction Cone Material Paper Surround Material Rubber Basket / Frame Material Steel Mounting Information Overall Outside Diameter 3.63" Baffle Cutout Diameter 2.76" Depth 0.86" # Mounting Holes 4 - All international buyers are responsible for all tax, duties and/or customs fees.