The string in these units is so thin it shouldn't be an issue, although it's just common sense to pick up after the shot. We put them in arrows many moons ago (1970's) when we had our archery shop, and they were a pain in the a$$ to get installed. I never used them myself. You have to mount a piece of velcro to the belly side of your arrow shelf for the tab to catch on and pull the string out. Usually that string will easily break with a pass through shot, as the animal runs. They seem to work okay though if the arrow stays in the animal.