| OMP — Negative Pressure Wound Therapy Powered Suction Pump | Class 2 / SU |
| OMR — Vessel Guard Or Cover | Class 2 / CV |
| OMS — Novel Influenza A Virus, A/H5 Ns1 Protein | Class 2 / MI |
| OMT — Absorbable Lung Biopsy Plug | Class 2 / AN |
| OMV — Ultrasonic Body Composition Analyzer | Class 2 / GU |
| OMW — Adhesive Backed Thermal Skin Patches | Class 1 / PM |
| OMX — High Demand, Revision, Semi-Constrained, Pyrolytic Carbon, Uncemented Finger Prosthesis | Class f / OR |
| OMZ — Pulmonary (Pulmonic) Valvuloplasty Catheters/Percutaneous Valvuloplasty Catheter | Class 2 / CV |
| ONA — Computer Assisted Hair Harvesting System | Class 2 / SU |
| ONB — Closed Antineoplastic And Hazardous Drug Reconstitution And Transfer System | Class 2 / HO |
| OND — Osmolality Of Tears | Class 1 / CH |
| ONE — Powered Light Based Non-Laser Surgical Instrument | Class 2 / SU |
| ONF — Powered Light Based Non-Laser Surgical Instrument With Thermal Effect | Class 2 / SU |
| ONG — Powered Laser Surgical Instrument With MicrobeamFractional Output | Class 2 / SU |
| ONJ — Dissolvable Gel For Preventing Ureteral Stone Migration | Class 2 / GU |
| ONK — Oral Lubricant | Class 1 / DE |
| ONL — Conformal Brachytherapy Source | Class 2 / RA |
| ONM — Radiant Infant Warmer Cabinet | Class 2 / HO |
| ONN — Intraoperative Orthopedic Joint Assessment Aid | Class 2 / OR |
| ONO — Neurosurgical Laser With Mr Thermography | Class 2 / NE |
| ONQ — Electrosurgical Coagulation For Aesthetic | Class 2 / SU |
| ONT — N95 Respirator With Antimicrobial/Antiviral Agent | Class 2 / HO |
| ONU — Drug-Eluting Peripheral Transluminal Angioplasty Catheter | Class 3 / CV |
| ONV — Electrical Impedance Spectrometer | Class 2 / SU |
| ONW — Hemodialysis System For Home Use | Class 2 / GU |
| ONX — Ovarian Adnexal Mass Assessment Score Test System | Class 2 / IM |
| ONY — Oral Removable Retainer For Weight Management | Class 2 / GU |
| ONZ — Mechanical Ventilator | Class 2 / AN |
| OOA — Hemorrhoid Prevention Pressure Wedge | Class 2 / OB |
| OOB — Drug-Eluting Percutaneous Transluminal Coronary Angioplasty Catheter | Class 3 / CV |
| OOD — Surgical Film | Class 2 / SU |
| OOE — Ophthalmic Femtosecond Laser | Class 2 / OP |
| OOF — Cryogenic Cord Blood Storage Container | Class 2 / HE |
| OOG — Knee Arthroplasty Implantation System | Class 2 / OR |
| OOI — Real Time Nucleic Acid Amplification System | Class 2 / CH |
| OOK — Dermal Cooling Pack/Vacuum/Massager | Class 2 / SU |
| OOL — Electronic Depth Gauge | Class 2 / OR |
| OOU — Parainfluenza Multiplex Nucleic Acid Assay | Class 2 / MI |
| OOW — Applicator For Rectal Suppository | Class 1 / GU |
| OOX — Automated Occult Blood Analyzer | Class 2 / HE |
| OOY — Bronchial Thermoplasty System | Class 3 / AN |
| OPC — Powder-Free Polychloroprene Patient Examination Glove | Class 1 / HO |
| OPH — Radiation Attenuating Medical Glove | Class 1 / HO |
| OPJ — Medical Gloves With Chemotherapy Labeling Claims - Test For Use With Chemotherapy Drugs | Class 1 / HO |
| OPL — Multiplex Immunoassay For Measles Virus, Mumps Virus, Rubella And Varicella Zoster Virus | Class 2 / MI |
| OPM — Multiplex Immunoassay For T. Gondii, Rubella, Cytomegalovirus And Herpes Simplex Virus 1 And 2 | Class 2 / MI |
| OPN — Auto-Antibodies; Phosphatidylserine, Prothrombin, Phosphatidylserine/Prothrombin Complex | Class 2 / IM |
| OPP — Pump, Infusion, Insulin Bolus | Class 2 / CH |
| OPR — Intrasaccular Flow Disruption Device | Class 3 / NE |
| OPT — Infrared Hematoma Detector | Class 2 / NE |