Inclusion Criteria:  Subjects must be at least 18 years of age. Subjects must have type 1 or type 2 diabetes mellitus. Subjects must be available to participate in all study visits. Willing to wear 1 Sensor on each upper arm simultaneously. Subjects must be willing and able to provide signed written consent. Subjects must be able to read and understand the device instructions. Subjects must be able to speak, read and write English.  Exclusion Criteria:  Known allergy to medical grade adhesive or isopropyl alcohol used to disinfect skin. Extensive skin changes or diseases at the proposed application sites.  Subjects who have or are:  Pregnant, A hematocrit level >37%, A condition requiring or likely requiring magnetic resonance imaging (MRI), computerized tomography (CT) or diathermy scheduled during the study, Participated in another clinical trial within 2 weeks prior to screening or are intending to participate in another clinical trial during the study. Unsuitable for participation due to any other cause as determined by the Investigator.