This item weighs 2 kg 1 piece 130mm high-end bass-midrange driver from Dego (Ehmann&Partner) T130/25/84/AI-e High-end bass-midrange driver for high tonal demands. The highlights: Highly damped steel speaker basket, ventilation under the centering spider, extremely stable all-aluminium diaphragm, butyl rubber surround, extremely long 25mm voice coil, gold-plated connection terminals, German brand product. Technical specs These data refer to a chassis Type designation T130/25/84/AI-e Manufacturer / Brand Ehmann & Partner / Dego Usage Woofer Cone Alu Surround Rubber Basket Sheet Steel Outer Diameter 130 mm Installation Diameter 110 mm Installation Depth 62 mm Hole Spacing 130 mm Magnet Diameter / Height 84 / 25 mm Voice Coil Diameter 25 mm Effective Diaphragm Area (S/m) 78.5 cm² Weight 1000 g Music Power RMS / Max. 85 / 170 Watt Impedance (Z) 4 Ohm Linear Frequency Response 85 - 2300 Hz Resonant Frequency ( Fs) 72.39Hz Average SPL (1W/1m) 87.19 dB Compliance (Cms) 0.51 mm/N Moving Mass (Mms) 9.51 g Mechanical Resistance (Rms) 1.14 kg/s Mechanical Grade (Qms) 3.79 Electrical Grade (Qes) 0.49 Total Grade (Qts) 0.43 Equivalent Volume (Vas) 4.4 dm3 DC Resistance (Rdc) 3.4 Ohm Coil Width 10 mm Drive Factor (BL) 5.5 Tm Reference Efficiency (No) 0.33 % Enclosed Enclosure   The TSPs are indicative and can vary up to 10% (normal tolerance). The data has been determined to the best of our knowledge and belief, but due to the amount of data and possible measurement, reading or typing errors, we cannot guarantee its accuracy