VINTAGE EBBCO Nautical SEXTANT ENGLAND Made Navigation Boating w/Booklet

Description

This is an old sextant made in England
It is an EBBCO brand sextant and comes with use and care booklet and original box.
I don't know anything about these things, but it seems like it has all the mirrors and such but it might be missing a bin for hole just above the Ebbco name?
Feel free to ask any questions I might be able to answer
Mirrors are intact, filters (?) are intact but may have some age damage?
Dial moves freely
Box has locking hook and is lined with foam rubber in good condition
There is an L shaped white wire piece that I'm not sure if it belongs with it or not.