I have an almost complete Cokin P filter collection from my analog photo-period. Now I switched Olympus MFT on. The Zoom 14 - 150mm has egg 58er filter thread. If the adapter ring only 0,1mm be too large or too small, the filter holder would be either turning to heavy or too light. In this original threaded ring is just right. That's why I prefer to spent a little more money than it would cost for one of these copies have been the case of China. I am very satisfied with the purchase.