The OvaView Standard Egg Candler is designed to be either hand-held or left on a work surface. Battery powered for convenience it uses high output high efficiency LED illumination which eliminates bulb replacement and concerns about egg overheating. It includes a flexible black ring to seal against the egg shell and a set of 4AA batteries. It is suitable for monitoring the embryo development of pale, plain shells (most species of hen, duck, goose, etc.). About Brinsea ProductsStarted over 30 years ago with a passion for breeding birds, Brinsea has made huge strides in the breeding industry with more patents than the rest of the small incubator industry combined, culminating in 2003 with the introduction of the world's first Contact Incubator. Each product is designed to offer a long lasting functionality as well as to be energy efficient. Brinsea operates from its own facility, manufacturing products from start to finish, engaging in the quality control process to ensure the highest quality product possible for their clientele.