Tape path guide
This assembly forms guides 4 and 5 of the tape path in a Sony SL-C9 / SL-C20 / SL-C24 / SL-C30 / SL-C40 / SL-F25 / SL-F30 / SL-HF100 / SL-HF150 / SL-HF950.

It is also responsible for pulling the tape out of shell and wrapping it around the head drum.

Loading and unloading completely fail.
Replacement of the shuttle assembly is not a trivial task as it involves stripping down the deck to gain access to the threading ring. This is best done whilst referring to a Sony service manual.