EST-1 Specs: 1" Neo Tweeter RMS power: 30RMS Max Power :60W Fo(Hz) 650 Nominal Inpedance: 4 Ohm Sensitivity @ 1W/1M (DB) : 90 Frequency Range: 650Hz-40KHz Voice Coil: 26MM Cone: Silk Cone Mounting Depth: 24MM Mounting Diameter: 49MM