Uniclife Aquarium Heater 180 lumens cool LED Light - Check the development progress of eggs and see the live embryo inside; Pocket-size , Sturdy aluminium alloy bodyDurable with easy on/off button Rechargeable 18650 2600mAh 3.7v Battery - Candling eggs anywhere! Even at a chicken coop which usually does not have any power outlet. This new version Battery-powered candler comes with a battery option (rechargeable); 3 Useful modes- High ,Normal ,Flashlight Great educational gift for kids who is having classroom project for hatching chicks.