Syorn Egg Incubators Egg Candler High intensity for Light & Dark Hatching Eggs Egg Torch Candling Light Egg candler Breeding Bird Great torch for checking if eggs are fertile. Easy to use Pen Style, simply press the clip on the side to turn the light on, easy to use one handed. The torch an be used to check fertility of eggs, which will show up approx 4 days after laying. Use in a dark room or nest box and point the torch at the side of the egg, it will easily light up and you can see what is inside your egg checking for blood veins and chicks We use this torch in our bird shed and wethink its great to use. Package includes: 1 X egg candler Batteries not included (you need to buy a 18650 battery/18650 = 18 mm in diameter and 65 mm in length)