To
measure your dog for a Martingale Collar, use a soft tape measure or a
piece of string and take the measurements at point A, B, and C in the
drawing below. Choose the size that fits within this range to
ensure that your collar fits perfectly.
For Sight Hounds, the
measurement at points A and B may be the same or very similar, this is
because their heads are often the same size or smaller than their necks.
For non-Sight Hounds, these measurements will be different and you will
need to choose a collar size that is large enough to slip over the head
(point A) but not too large to fit correctly at point B.
In other words, choose
the smallest size that will still fit your dog. If your dog has a
15 inch neck, choose the Medium, which is adjustable from 13-18 inches
rather than the Large, which is adjustable from 15-20 inches.