The Superior 2" 90-Degree Multicoated Erecting Prism diagonal takes advantage of a wider field of view through the use with 2" eyepieces. This gives astronomers a great view of the illustrious stars and the magnificent heavens above. The body of the cool sleek prism is made of finely machined aluminum, which provides a lifetime of durability and steady viewing. The Superior includes an adaptor to attach 1.25" eyepieces.