Brand NEW! Including 90 Days USA Factory Warranty. Dayton Audio Reference Series RS100-8 4" midbass speakers deliver exceptional clarity, detail, and dynamics?and of course, incredibly low distortion. Key Features One of the lowest distortion, highest resolution driver series available Low-distortion high-excursion motor system with two short-circuit paths Compliant suspension and rigid black anodized aluminum cone for strong bass performance Heavy-duty 6-hole cast frame, low-loss rubber surround, and solid aluminum phase plug Designed and engineered in the USA The Dayton Audio Reference Series was conceived with one goal in mind?low distortion. Each speaker was carefully designed and optimized to offer the highest performance with the lowest distortion levels. At the same time, by focusing on features that contribute to sound quality and eliminating unnecessary frills, the drivers offer value unparalleled in the industry. Dayton Audio Reference Series RS100-8 4" midbass speakers deliver exceptional clarity, detail, and dynamics?and of course, incredibly low distortion. Product Specifications Nominal Diameter 4" Bolt Circle Diameter 3.54 Power Handling (RMS) 30 Watts Power Handling (MAX) 60 Watts Impedance 8? Frequency Response 90 to 20,000Hz Sensitivity 84.6dB 2.83V/1m Voice Coil Diameter 1" Thiele-Small Parameters Resonant Frequency (Fs) 92.2Hz DC Resistance (Re) 6.4? Voice Coil Inductance (Le) 0.5mH Mechanical Q (Qms) 2.37 Electromagnetic Q (Qes) 0.76 Total Q (Qts) 0.58 Compliance Equivalent Volume (Vas) 0.05ft Mechanical Compliance of Suspension (Cms) 0.82mm/N BL Product (BL) 4.2T·m Diaphragm Mass Inc. Airload (Mms) 3.63g Maximum Linear Excursion (Xmax) 3.5mm Surface Area of Cone (Sd) 35.3cm Materials of Construction Cone Material Aluminum Surround Material Rubber Voice Coil Wire Material Copper Voice Coil Former Aluminum Basket / Frame Material Cast Aluminum Magnet Material Ferrite Mounting Information Overall Outside Diameter 3.86" Baffle Cutout Diameter 3.04" Depth 2.01" # Mounting Holes 6 Optimum Cabinet Size (determined using BassBox 6 Pro High Fidelity suggestion) Sealed Volume 0.04ft Sealed F3 136Hz Vented Volume 0.1ft Vented F3 67Hz - All international buyers are responsible for all tax, duties and/or customs fees.