The Middle one seems to be a standard quite new with no instalation marks and the numbers 100P-1372 and words Top/End.
But what are the other two for/from? The one on the far left has the consistency of a sponge rubber ball and can be squeesed between the finders...deffinately not nylon or plastic.
The one on the right has two more vanes and is made out of brass/bronze.
I am trying to sort out a number of these bits and would like to put a tag on them before putting away for future seagull explorers.