It looks like a bracelet is enough depending upon the jurisdiction in the United States. For example in New York - https://www.health.ny.gov/professionals/ems/

It looks like a bracelet is enough depending upon the jurisdiction in the United States. For example in New York - https://www.health.ny.gov/professionals/ems/policy/99-10.htm https://www.health.ny.gov/professionals/ems/policy/99-10.htm