USING TOOLS:
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Step 1: Grab a flexible cable (e.g. usb cable) and a ruler. Align the left side of your cable with your lower left ear as shown in the image. If you’re using tailor’s measuring tape, align the left side of the measuring tape behind your left ear in the same way.
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Step 2: Hold the end of the cable/measuring tape steady on the left side and pull the right side along the back of your head until it meets your right ear. Mark the point.
Step 3: Remove the cable/tape from behind your head, straighten the cable/tape and read the length.
If your measurement is 9.25 inches or shorter (23.49 cm), OpenRun Mini will fit you best.
If your measurement is more than 9.25 inches(23.49 cm), OpenRun will fit you best.