1. High-intensity egg light is used to control the development of eggs and helps to observe the growth of fertilized eggs. 2. After the incubator has been running for a few days, you can scan the inside of the eggshell with a bright light, and you can see the dark spots and textures of the fertilized eggs. 3. Powered by 3 AAA batteries (not included), it is lightweight, compact and portable, and easy to use. 4. The egg light flash provides bright cold light, providing ultra-safe lighting for your eggs. 5. The cold light tester is not only suitable for people who want to hatch eggs, but also for children and students to learn the hatching process. Suitable for fun classes or school laboratories.