STEP 1
Check Credit/Debit Card Calibration
Hold any standard credit or debit card flat against the box below. Adjust the slider until the dashed outline matches your physical card width exactly.
Standard Card (85.60 × 53.98 mm)Align card edges to match width275 px
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STEP 2
Paper Measuring Strip (Cut Out)
Cut along the outer dotted lines, slice the small vertical slot `[ | ]`, wrap snugly around your finger base, and pull the tapered end through the slot.
SLOT [ | ]
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STEP 3
Ring Circle Match Matrix
Place an existing ring that fits you comfortably over these circles. The black line must align exactly with the inside diameter of your ring.
US 414.9 mm
US 515.7 mm
US 616.5 mm
US 717.3 mm
US 818.1 mm
US 918.9 mm
US 1019.8 mm
US 1120.6 mm