Parker Crossbows RED HOT Lighted Green Capture Nocks are designed for use with the newest and best technology. These can handle the power and speed of any crossbow on the market. The patented design is super accurate and as safe as possible. The high visibility green LED is great in low light or no light situations. Even if you leave before dark or are a day hunter, this nock can save your butt if youre tracking something into the night. This past year I took a shot as the lighting was getting low. I gave it the required time and went to go look for my arrow and sign of a hit, but couldnt find a thing in that dense woods. I looked for a long time, but didnt end up finding the 7 pointer until the next day. Thankfully it was a cool night and there were no coyotes in the area. Don't test your luck like I did, pick up a set, or even one of these nocks and prevent the loss of game.