The EYE-SHIELD is a flexible molded rubber material that connects to the eye piece of the binocular. The EYE-SHIELD cradles your eye and prevents ambient light from entering into the space between your eye and the binocular eyepiece that causes lens glare. An added benefit is the EYE-SHIELD protects the eyes from wind, rain, snow and dust. This is a must have for everyone who uses binoculars.