Earphone board set EP91

Listed on the following equipment:
Horizon - G7 - (FC203)
Matrix - Ascent Trainer - A3xe - Silver - (EP606)
Matrix - Hybrid Cycle - H7xi - (CB93, EP614D)
Matrix - Hybrid Cycle Premium Series - H7x-01-G4 - (CB72, EP91)
Matrix - Premium Series - U7x-01-G4 - Silver - (CB75, EP91)
Matrix - U3xe - U3xe - Silver - (CB75B, EP604)
Matrix - U7x - U7x - Silver - (CB75B, EP91C)
Matrix - U7x - U7xe - Silver - (CB75B, EP92F)
Matrix - U7xi - U7xi-02 - Silver - (PCB92-US-F, EP614D)

* Images may not be identical to part.