Kenko Mirror Lens 500mm F6.3 DX Focal Length: 500mm Aperture: F6.3 (fixed) Lens Construction: 6 groups, 7 elements Minimum Focusing Distance: 2m Filter Diameter: 34mm Maximum Diameter: Φ98mm Length: 122mm Weight: 705g The mount is a T-mount (pitch 0.75mm, diameter 42mm) with an interchangeable mount system. Included Accessories: Front lens cap, rear lens cap A Pentax mount (sold separately) is included. (See photo XX) It can be attached to any manufacturer's camera if you prepare another T-mount. Thank you. #Kenko #MirrorLens #500mm