Opteka 500mm f/6.3 HD Telephoto Mirror Lens for Sony Alpha A99, A77, A65, A58, A57, A55, A37, A35, A33, A900, A700, A580, A560, A550, A390, A380, A330 and A290 Digital SLR Cameras High-index / low-dispersion optical glass, fully multi-coated, every element, anti-reflection coating 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 May be combined with the Opteka 2x multiplier for 1000mm (Sold separately - 47st Photo Item Code: B000JSZ41S)