White things at bow

Always wondered what are the two white objects at the very front of the bow basically in the movie what jack uses to stand on during his whole king of the world. Do they serve a purpose or just design
Good day to you,


The two white objects are part of the fairlead block. A fairlead is a fitting at the outer edge of a deck, used to change the direction of a hawser so that it is delivered properly to the bitts or capstans for mooring or warping.

Yours sincerely,