The long side should be two feet, and the short side should be one foot.
Put the squares together, as shown.
Hold the squares, as shown, and lay the longer end against the horseâ€™s shoulder, where the collar would lay.Â (You may have to feel where the shoulder bone is located to know where the larger part of the square should lay). Slide the squares together so the top portion touches the top of the neck, and the bottom portion touches the bottom.
Measure the distance between the squares.Add about 1/2 to 3/4inch for clearance and select that collar size.
See the MEASUREMENTS page.