Rokinon 500/1000mm F6.3 Mirror Lens for Canon EOS Mount Aperture: F6.3 Fixed Optical Construction: 7 Elements in 6 Groups Angle of View: 5 Degrees; Minimum Focusing Distance: 2.0m(6.1ft) Filter Size: 95mm Focus Type: Manual; Mount: T-Mount Adapter (Included for Canon EOS Mount) Includes: 2X Teleconverter Lens