This is a genuine Black and Decker replacement part, it is sold individually.
This part is used in the Black and Decker GH710 Type 1 Trimmer.
It includes the Spool Lever, and Eyelets.
To remove this part, press on the two tabs that extend into the spool housing.
Then to install it, line up the tabs with the slots in the spool housing and press it in.