The 89-487 is a 30mm diameter metallic mirror, sourced from the reputable vendor Edmund Optics. This mirror is designed to protect silver coatings, offering a broad wavelength range of 450-10000nm, and is particularly effective at 588nm.
The mirror's geometry is circular, with a thickness of 3mm, and it is constructed from soda lime ru clear material. The coating on the front is EDM DPROTSIL3001000, which is specifically designed to protect the silver coating.
This mirror is classified as a thin lens, and according to the vendor's website, it is currently in stock and available for immediate purchase. The mirror's web links are valid, leading directly to the product page on the Edmund Optics website.