Here's a 3D printed bracelet that I designed for my daughter, and I've made it available for all my diabetic friends. The bracelet has an easy-open side-release latch. Bracelet has a 2.5" inside diameter when closed and is available in a variety of colors. Will gladly make additional sizes available.
NOTE: I am donating 100% of the profits from sales of this bracelet to the American Diabetes Association.