Feature:1. Compatibility: The arrows lighted nocks is suitable for the shaft with an inner diameter of 6.2mm, which can meet the needs of people2. Plastic Material: The shell is made of hard plastic material, strong and durable, hard texture, not easy to damage, long service life3. Simple Operation: The arrows lighted nocks are simple, easy to understand, without the aid of tools, clamping shaft can be used4. Automatic Lighting: The tail of the luminous arrow can be automatically lit and manually closed. The light is stable and the LED lamp has a long service life5. Excellent Accessory: The arrows lighted nocks can help us see the path of the arrow clearly at night, so that we can quickly locate, is a practical accessorySpecification:Item Type: Lighted Nocks for ArrowsProduct Material: PEWeight: Approx. 19g / 0.7ozLength: 4.5cm / 1.8inBattery: Built In Button BatteryModel Number: SR416SWCapacity: 8mah.Package List:3 x Lighted Nocks for Arrows