This will be a non-randomized, single-armed study conducted in the United States. Following screening, a minimum of 60 to a maximum of 80 subjects at up to 4 clinical sites will be enrolled. All participants will wear the G4 Sensor for one 7-day wear period (~168 hours). A subset of 20-30 subjects will wear two G4 Systems (one of which will be blinded) during the 7-day wear period for the purposes of assessing precision. During home use, subjects will be asked to use the meter provided to them to take fingersticks for calibration and diabetes management. Subjects will also be asked to confirm high and low G4 System glucose alerts/alarms by taking a comparative fingerstick immediately after receiving an alert/alarm.