With its unique design， the Brinsea OvaScope Bird Egg Candler creates a clearer view of each egg’s interior so you can monitor your feathered friends’ growth. This candler completely blocks out ambient light， and the result is a slightly magnified image of the egg that’s clearer and more easily visible. Because you can attach a webcam to the OvaScope， it’s ideal for teaching purposes. You can even rotate the egg smoothly as you look at its interior. High-efficiency LED illumination means there are no bulbs to worry about replacing and no risk of overheating the egg. This candler is suitable for any egg size up to goose eggs. The included small black ring can create seals against smaller eggs. This candler is powered by the four included AA batteries， though you can also choose to use rechargeable batteries.