Designed for greater efficiency in low light, enhanced precision, and vastly improved retrieval, Nockturnal Universal Fit Lighted Nocks help you take aim at improving your archery. These ultra-strong polycarbonate nocks feature Nockturnal's game-changing shot-activated lighting system to retrieve your arrows with incredible ease and pinpoint accuracy. Each lighted nock provides 20+ hrs. of battery life to accommodate extended trips. Have you seen the light? With Nockturnal Nocks, you will, every time.