Study of GLUCUBE Performance, a Non-invasive System for Monitoring Blood Glucose Levels Based on Near Infrared Spectroscopy (NIRS) Technology.

Inclusion Criteria:

1. Be ≥ 18 years old.

2. Have a smartphone with an internet connection that allows the installation ofGLUCUBE APP

3. Have signed the informed consent.

Exclusion Criteria:

1. Subject is currently participating in another clinical investigation or hasparticipated in another clinical investigation in the past 30 days prior to thestart of the present study.

2. Pregnant or nursing subjects and those who plan pregnancy during the clinicalinvestigation follow-up period.

3. Presence of other anatomic or comorbid conditions, or other medical, social, orpsychological conditions that, in the investigator's opinion, could limit thesubject's ability to participate in the clinical investigation or to comply withfollow-up requirements, or impact the scientific soundness of the clinicalinvestigation results.

4. Patients with any acute active and/or infectious disease.

5. Patients who have a condition that affects blood circulation in the fingers of thehand, such as Raynaud's phenomenon.

6. Any medical condition that, by the investigator judgment, will increase the riskfrom hyper and hypoglycemic event: seizures, heart disease, hypoglycemiaunawareness, etc.

7. Patients who, in the opinion of the investigator, do not have sufficient manualdexterity to perform the tests themselves.

8. Patients with an inability to maintain stability of the hand during measurement orwith progressive disease of the nervous system that affects movement (Parkinson'sdisease, moderate-severe essential tremor, and other diseases with involuntarymovements).

9. Patients suffering from calluses, malformations, or open wounds with bandages.

10. Patients with nail polish or any type of false nail.

11. Subjects who do not understand or cannot follow the Procedures Involved in the Useof the Device Under Investigation.