Hi this is a brass shavings basket for the RCBS Case Trimmer. 

 (Note not for the rcbs trimmer 2)  rcbs trimmer 2 version is in my ebay store

Catch your brass shavings in the basket to avoid a messy work area.

Also has a build in holder for your pilot pins, (just slips over the edge of the tray)

Simply place the basket in place and that is it.

This item is 3d printed by me. 

Thanks for looking.

Trimmer and pilot not included. Just the 3D printed parts