Place your artwork on the band and see it at true proportion before you order. Drag to move, use the corner handle to scale and rotate. The whole band prints — the marks beneath it show where the lock sits once the band is worn.
Why this matters: the JSON records where each element sits in millimetres, and which file it came from. Production rebuilds the layout at print resolution from those originals — a PDF stays vector — so nothing is printed at screen quality.