[Compatibilities] Keuaaao X lighted nocks fit arrows with .204 Inside Diameter, bushings matching and easy installation [Brightness] These nocks emit a vibrant and highly visible light, making it easier to track your arrows during low-light conditions, including darker evenings and winter months. They help in observing arrow trajectory, enhancing accuracy and retrieval [On/Off] The light activates automatically upon release when contacted by the bowstring, featuring a linear switch design. A slider switch allows for easy deactivation [Battery Life] Long-lasting battery life provides up to 48 hours of continuous illumination. The LED remains bright even in daylight conditions [Practicality] These lighted nocks are ideal for archery hunting, target shooting, 3D tournaments, and low-light environments. They assist in tracking flight path and locating arrows quickly. A great choice for archers seeking improved shot visibility Color: Red Material: Plastic Package Contents: 12PCS x Lighted Nocks for Arrows Note: Light reflection and different display settings may cause slight color variations between the image and the actual item. Measurement may vary by +/- 1-3cm