Durable, flexible, lightweight soft rubber with an ergonomic oblique eye cup that provides ample padding and eye protection. Reduces glare, helps prevent eye strain, and protects eyes from damage in bright light. Extends over the glasses to deliver a comfortable cushion and secure fit. This rubber eye guard/eye cover protects the eye area and fits most optical instruments with eye relief sizes from 36 mm to 43.5 mm. Compatible with a wide range of devices, including binoculars, riflescopes, spotting scopes and other optical instruments within the stated eye relief range. Use scenarios: - Outdoor birdwatching or hiking in bright sun, using binoculars to reduce glare and protect the eyes. - Astronomy or wildlife viewing with spotting scopes or telescopes during long observing sessions. - Shooting or surveillance requiring eye protection while using riflescopes or similar equipment.