carstenw is right, it´s the second version of Elmarit 180/2.8, my copy is VERY SHARP even on wider apertures, minimal or no visible CA, it´s better than 1. version which has "shorter" focusing ring and a tripod stand, version II doesn´t have it. APO 180/2.8 would be great but costs to much for me. APO 180/3.4 is better and focusing is easier and quicker to achieve focus than with non APO versions. If you can live with minimal f/3.4 instead of f/2.8 I ´d buy APO 180/3.4, it´s "Made in Canada" only.