This Is A Brand New Aftermarket Diaphragm , "Titanium" For : P Audio: BMD-740, BMD-750, (Series 1 Only) BM12CX38, BM15CX38 Turbosound: TXM-15M, TXM-252, TXD-15M, CD 210, CD 212, RD 210, RD 212 Please Look And Make Sure The Diaphragm You Are Ordering Matches The Pictures Above & The Specs Below Specs: Overall Diameter: 4.31" (110 mm) Voice Coil Diameter: 2.87" (73 mm) Diaphragm Material: Titanium DCR: 6.2 Ohms Nominal Impedance: 8 ohms