Item Type: Egg Tester Material: Metal, Plastic Application: Cool Light Egg Tester Applicable Object: Chickens, Geese, Quails, Ducks, Pigeons, Birds, etc. Battery Type: 3 x AAA Dry Batteries (not included) Egg Detection Method: The First Test: Chicken embryos hatched for 5 to 6 days, duck embryos for 7 days, and goose embryos for 8 days. The purpose is to observe the development of embryos and select infertile eggs. Dead and cracked eggs. At this time, the embryo develops normally, the blood vessel is clear, and it is radially distributed. The expansion surface accounts for about 4/5 of the egg body. When the egg is defatted, there are evident black spots, commonly known as "single beads". The Second Test: Chicken embryos were performed over 10 days, and duck embryos and goose embryos were performed over 20 days. 1CONE SPOT LIGHT The egg candler tester has cone spot light design, High battery life and high brightness. 2DETACHABLE STRUCTURE The LED light egg tester structure is detachable, easy to operate and easy to carry. 3COOL LIGHT Cool light radiation does not damage breeding eggs, providing a brighter and cooler light source. 4SAFE OBSERVATION Does not carry the danger of damaging the development of the embryo and the observation process is safer. 5MULTIFUNCTION USE Not only for those who want to do eggs hatching, but also for children and students to learn the hatching process. 1 x EggTester (Battery Not Included) 1 x Lampshade