Amici prism (31.7mm, 1.25") with 45-degree viewing
This is a 45° viewing angle amici prism.
These are good quality 1.25" Amici prisms which can be used for bird watching or night sky observation with equally good result. Amici prisms supply an upright standing and sidecorrect picture. They give high contrast and good sharpness.
Celestron Diagonal, Erect Image - 1.25 in - 45°