Cardstock Calibration Tool V3

One canonical black-only 11 x 17 inch scored cardstock sheet reused in every view.

1. Flat As Mailed

The customer receives one flat scored sheet with punch-out paper feet.

FOLD HERE PUNCH OUT FOOT PUNCH OUT FOOT

2. Folded Upright

Same sheet. Two punch-out tabs hold the vertical half at 90 degrees.

3. Deployed Beside Steps

Same sheet placed at the stair edge to give horizontal and vertical scale.

4. App Detection View

App UI adds color; the physical prop stays black-only and machine-readable.

Tool detected Hold steady