Replacement Diaphragm Mackie 0013925 DN10/1704-8, SN-D44 For SA1530, SA1532Z Voice Coil Diameter : 44.4mm / 1.75" Impedance : 8 Ohm Outer Ring Diameter : 100.55mm / 3.95" The Center Distance Of The Two Post Terminals : ~82.14mm / 3.23"