FR 10 - 4 ohm FR 10 - 8 Ohm FR 10 F 4 OHM FR 10 F - 4 Ohm FR 10 HM - 4 ohm FR 10 HM - 8 ohm FR 10 HM 4 OHM FR 10 HM 8 OHM FR 10 HMP - 4 Ohm FR 10 HMP, 4 OHM