glucometer case

I wanted a case for my glucometer (Freestyle) where i can pick a probe stick place it in the meter, pinch myself and take the sugar measure without opening the box and everything spreading everywhere (specially in the morning)
I am not and expert in hinges, this is my first one, and added a little hole for a magnet to keep the case closed.
for the axys of the hinge y used a little piece of filament.