SS Audio Diaphragm 4-Pack for Foster Horn N30, 025, H025, N27, N28, and many others Premium SS Audio Diaphragm 2-Pack for many Foster, Fostex, Cerwin Vega, Roland, and SWR models. Specs: Voice coil: 1" (25mm), Diameter: 1-3/4" (45mm), Length: 2-7/8" (72mm), Impedance: 8 ohm, DCR: 7 ohm SUPERIOR quality, LARGEST selection, and the BEST prices! FREE technical support. FAST & FREE shipping to any USA address. To get the BEST quality repair parts, be sure to buy ONLY from SS Audio and Simply Speakers. Thank you!