all the arrow flight issues I was having.. now since I have tuned my bow to shoot alot better, still nees work but, slick tricks fly great. I found a Cx 300 at the range that was shorter than my arrow so it must be lighter. it shoots great out of my bow. All this under spined crap I got from ther shop and here I can shoot a 300 now, that fly's great. one more thing to add to the confusion.