The numbers shown in the photo (4.0, 3.2, 2.25) refer to the wire gauge (thickness) of your prong collar links in millimeters (mm).
To choose the correct ClicLock, you must select the same wire gauge as your current prong collar.
How to Identify Your Size
Look at one individual prong link on your collar and compare it to the photo:
-
4.0 mm → Thickest links
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3.2 mm → Medium thickness
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2.25 mm → Thinner links
The coin in the image shows the size difference for easy comparison.
Important
This accessory must match your prong collar’s wire gauge exactly.
If you select the wrong size, it will not fit properly.
If you’re unsure which size you have, measure the length of one prong link and compare it to the photo.

