Inclusion Criteria:  Type 1 or 2 diabetes mellitus Male or female age ≥ 18 years old and ≤ 70 years old Willingness to adopt measures to prevent water coming into contact with the device sensor (e.g. abstain from swimming, sauna, avoid hitting the sensor with direct jets of water) Ability to communicate with the investigators, able to operate medical device after training and comply with the testing procedures outlined in this protocol (including, but not limited to, willing to wear the continuous glucose monitor and testing capillary blood glucose) Subjects who show understanding of the study procedures and willing to sign a written informed consent form.  Exclusion Criteria:  Hospitalization due to diabetic ketoacidosis or severe hypoglycemia, within 3 months prior to screening HbA1c >13% or urine ketone 3+ Use of pacemaker Body Mass Index (BMI) ≤18.0kg/m2 Extensive skin changes/diseases that preclude wearing the required number of devices on normal skin at the proposed application sites, i.e. upper arm or abdomen (e.g., extensive psoriasis, recent burns or severe sunburn, extensive eczema, extensive scarring, extensive tattoos, dermatitis herpetiformis) Any psychiatric disease such as depression or anxiety Any severe hepatic, renal, cardiac, cerebral, respiratory or neurological diseases (e.g. serum ALT, AST, Creatinine level ≥3 times the upper limit of normal) Has a MRI scan, CT scan or other procedure requiring the subject be under strong magnetic or electromagnetic environment, scheduled during the proposed study participation Blood loss >400ml in the past 3 months (including blood donation) Have a known allergy to medical-grade adhesives, or known hypersensitivity to any of the products used in the study Difficulty in sampling venous blood or cannot tolerate venipuncture Participated in other investigational studies in the past 3 months Currently pregnant or lactating women, or positive pregnancy test Any condition that, in the opinion of the investigator, renders the subject not suitable for the study.