Neck rope made of double 6 mm (1/4") ropes that is tied the same way as a rope halter and can be adjusted steplessly.
The length you choose is the maximum length of the neck rope when it is tied. You can make the neck rope much shorter than the maximum length but not longer, so if you are unsure which length to choose I recommend that you choose a larger size to ensure that your neck rope will not be too short.
The tie end is whipped with thin twine to keep the two ropes together. If you want a completely solid-colored neck rope you can choose the same color for the whipping as the neck rope or you can choose a different color for a nice contrast.