Long focal length eyepiece. Focal length: 35mm. Levenhuk Ra 2 ED 35mm Eyepiece is a parfocal eyepiece. Its main advantage is long focal length of 1.4 inches. The eyepiece's optics are fully multi-coated and made of ED glass. The lenses' edges have blackening that provide high-quality clear views of regular or even very bright objects. This model has a light weight due to an aluminum shell. Despite its 2" barrel diameter, you can attach the eyepiece not only to 2" barrel diameter focusers but also to those with a barrel diameter of 2" using a 2" to 1.25" adapter.