Roof Tiles

Who knew there could  be so many very similar but subtly different variations of roof tile design?  The installation of a new boiler required the original vents to be removed from the roof, and the tiles replaced.  I had bought replacement tiles, but they proved to be the wrong ones.  When I visited a roof tile stockist, he offered me two different tiles as he couldn't identify the correct one from my photographs.

I think I have now identified which is the correct replacement and hope to buy them and get them installed next week.