Hi this is a brass shavings basket for the (old style) LE Wilson Case Trimmer.  

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

Simply place the basket in place and that is it !
Both parts are held in place by very strong magnets.

NOTE: This will not work on newer models that are made of aluminum (magnets will not stick to it)
This item is 3d printed by me. 

Thanks for looking.

Case Trimmer Not included. Just the 3D printed parts
Other model versions are available in my  store