Opteka 500mm/1000mm f6.3 HD Telephoto Mirror Lens for Panasonic Lumix DMC G9, GH5, GX850, G85, GX8, G7, GM5, GH4, GX7, GH3, GH1, Olympus Pen E-PL7, P5, PL5, PM2, PL2 Micro Four Thirds Digital Cameras High-index / low-dispersion optical glass, fully multi-coated, every element, anti-reflection coating Manual focus, digitally-optimized telephoto zoom lens 7 lens elements in 6 groups Incredibly compact and lightweight Great for the wildlife or nature photographer who wants to be hidden while taking photos of the subject