Cerwin Vega H25
It fits the H25, HO25, HO-25B, H25F, HO25F
Overall Diameter: 1.77"
Length: 3.09"
Voice Coil Diameter: 1.00"
DCR: 7.9 ohms
Impedance: 8 Ohm
This diaphragm is very similar to the Foster diaphragm but the Cerwin version is longer.