Test it now
This is the exact code that will be printed. Point your phone's camera at it — if it opens the right thing here, it will on the sign.
Why it scans. Every dark square of the code is a pocket in the sign's face filled flush with the second color — no ink, no sticker, nothing to fade. A plain margin around the code (the "quiet zone" scanners need) is kept clear, and we refuse to shrink the squares below what a printer keeps crisp; if your content is too long for the size, we'll say so instead of printing something a phone can't read. 4 mm thick; flat back for tape or a stand, or two screw holes.