Brand NEW! Including 90 Days USA Factory Warranty. Dayton Audio's DMA70-PR 2-1/2" aluminum cone passive radiator allows you to tune small enclosures lower than possible using conventional ports. Matching the DMA series of drivers drivers perfectly, this passive radiator is perfect for use in ultra-small designs like smart speakers, sound bars, and portable Bluetooth speakers. Highlights Perfect match for the Dayton Audio DMA series drivers Allows tuning small enclosures lower than possible using conventional ports Rear mounted threaded post allows easy mass adjustment for custom tuning DIY friendly, oversized mounting flange makes installation simple Dayton Audio DMA70-PR 2-1/2" DMA Series Passive Radiator The DMA70-PR 2-1/2" passive radiator from Dayton Audio is the perfect option for achieving low tuning frequencies from the smallest enclosure designs. This incredibly small passive radiator has all the features you would expect lager units including adjustable mass, aluminum cone, and rubber surround. Visually identical to Dayton Audio's full-range DMA series drivers, the DMA70-PR can also be used with any small driver that requires a low tuning frequency. The threaded rod and included wing nut on the back of the cone makes it easy to add mass to tune the radiator as needed for your projects. Whether you are building a smart speaker, sound bar, or portable Bluetooth speaker, the Dayton Audio DMA70-PR introduces a new range of possibilities. Specifications: ? Fs: 34.5 Hz ? Vas: 0.046 ft (1.32 liters) ? Qms: 3.86 ? Cms: 1.77 mm/N ? Mms: 12.0 g ? Rms: 1.49 kg/s ? Sd: 22.9 cm ? Xmech: 7 mm ? Dimensions: Overall diameter: 2.75" x 2.75", Cutout diameter: 2.52", Depth: 1.73". Product Specifications Nominal Diameter - 2-1/2" Thiele-Small Parameters Resonant Frequency (Fs) - 34.5 Hz Mechanical Q (Qms) - 3.86 Compliance Equivalent Volume (Vas) - 0.046 ft. Mechanical Compliance of Suspension (Cms) - 1.77 mm/N Diaphragm Mass Inc. Airload (Mms) - 12.0g Maximum Linear Excursion (Xmax) - 7 mm Surface Area of Cone (Sd) - 22.9 cm Materials of Construction Cone Material - Aluminum Mounting Information Overall Outside Diameter - 2.75" x 2.75" Baffle Cutout Diameter - 2.52" Depth - 1.73" Bolt Circle Diameter - 3.25" # Mounting Holes - 4 - All international buyers are responsible for all tax, duties and/or customs fees.