This Is A Brand NEW Aftermarket BMS 4550 Driver. For Yorkville 7402 Replacement 16 ohm Diaphragm. Used In 2152, U15B, U159. Please Look And Confirm The Diaphragm You Are Ordering Matches The Pictures Above & The Specs Below. Specs: Overall Diaphragm Diameter: 3.71" (94.4mm). Voice Coil Diameter: 1.75" (44.4mm). DCR: 12 Ohms. Nominal Impedance: 16 ohms. Most Orders Placed Before 3PM and Paid thru PayPal Are Shipped The Same Day; Monday to Friday.