Not totally, but they do afford some protection to the rear of the arrow. What they also do is help keep the arrow from splitting if you are one who likes to bust nocks.
Originally Posted by gravedigger
For the most part I have used CB busings and G-nocks for about 15 years now. Although smaller than UNI bushings they are intended for use in most common size carbon arrows. Along with the protection afforded I am of the opinion that G-nocks are better quality than most nocks, being more uniform in groove size from lot to lot.
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