This spring was super awesome. I put it in my kronos and after I actually managed to load it, I shot it off my balcony and the round went an entire 3/4 of a block. The only thing wrong with this spring thought is that it was too hard to prime and I'm just a kid, so it was pretty hard to pull the slider back. It works great for adults with stronger arm muscles, but overall, the performance I got out of the spring was phenomenal. I would say if your an adult who still uses nerf, definitely buy this spring it works great. but if your just a kid, do not buy this spring the prime is really strong.