Overall Diaphragm Diameter:  2.75"
Voice Coil Diameter:  1.75" with titanium dome.
Impedance:  8 ohms.
Here is the list of some of the model #'s:
Berhinger: 44P60A-8
Mackie: DC10/1701-8, SRM-450 version 1, C300Z, 0008093, 0025666, SA-1521, SR-1522, S-215, S-225, S408
P-Audio: BMD-440, BMD-450