Upgraded version of the switch, more stable to use, will not before Automatically turn on when you ; Push up by hands without dismantle if you want to turn off With lithium batteries perfect for hunting at dusk with 48+ hours of battery life,easily to track your arrows at night or daytime Designed for greater efficiency in low light, enhanced precision, and vastly improved retrieval,Help you take aim at improving your archery accuracy Flashing high-visibility light makes it easier to find your Work for: Aluminum shafts & carbon shafts & glassfiber shafts. Material:PC colour:red Package Contents: 3 x 4.2mm luminous nock 3 x 5.18mm conversion ring 3 x 6.2mm conversion ring Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.