This Is A Brand NEW Compatible Aftermarket Replacement Diaphragm with Stud or TAB Terminals That Will Fit Altec 288, 291, 299 and 299-AT Driver and Horn 25884XX & 23763 Specs : Overall Diaphragm Diameter: 4 1/8 - 105mm Voice Coil Diameter: 2 7/8 in - 73mm Impedance: 8 ohms DCR 6 ohms Aluminum dome with edge wound voice coil on Nomex Tape Aluminum Edge Wound Wire FREE SHIPPING ONLY In The USA. Most Orders Placed Before 3PM and Paid thru PayPal Are Shipped The Same Day; Monday to Friday.