Egg Tester LED Cool Light Egg Candler Lamp Incubator for Duck Eggs Goose Eggs Crane Quail Eggs Bird EggsBlue 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.