0.5x focal reducer halves the focal length of a telescope to deliver a wider field and brighter of view.  

Easily threads into standard 1.25" eyepieces, camera adapters, and other accessories.

Lens is fully multi-coated lens in a black-anodized aluminum filter cell

Generally, the 0.5x focal reducer is often used together with 1.25" eyepieces.  Please be aware of the focuser traveling range in other application.