Inclusion Criteria:  Subjects aged 5 to 11 years of age with the following audiometric criterion:  A conductive or mixed hearing loss and still can benefit from sound amplification. The pure tone average (PTA) bone conduction (BC) threshold (measured at 0.5, 1, 2, and 3 kHz) should be better than or equal to 55 dB HL. OR A profound sensorineural hearing loss in one ear and normal hearing in the opposite ear (i.e., single-sided deafness or "SSD"). The pure tone average air conduction hearing thresholds of the hearing ear should be better than or equal to 20 dB HL (measured at 0.5, 1, 2, and 3 kHz). Prior experience with amplified sound through properly fitted amplification device such as a hearing aid, a CROS device, or a bone conduction device on a softband or sound arc. Parent or Legally Authorized Representative who is willing and able to provide written informed consent for the study participant.  Note: Subjects may include individuals seeking new implantation unilaterally (in one ear) or individuals already implanted with a bone-anchored device seeking a second-side implant (sequential bilateral)  Exclusion Criteria:  Insufficient bone quality or quantity to support implantation of both the BI300 Implant and the OSI200 Implant. Chronic or non-revisable vestibular or balance disorders that could prevent benefit from the device, as determined by the investigator. Abnormally progressive hearing loss. Evidence that hearing loss is bilateral retro cochlear or bilateral central origin. Evidence of conditions that would prevent speech recognition improvement as determined by the investigator. Skin or scalp conditions that may preclude attachment of the Sound Processor or that may interfere with the use of the Sound Processor. Unable or unwilling to comply with the requirements of the clinical investigation as determined by the Investigator. Investigator site personnel directly affiliated with this study and/or their immediate families; immediate family is defined as a spouse, parent, child, or sibling. Cochlear employees or employees of Contract Research Organizations or contractors engaged by Cochlear for the purposes of this investigation. Currently participating, or participated within the last 30 days, in another clinical investigation involving an investigational drug or device that could impact the safety or effectiveness of the Osia 2 system as determined by the investigator.