This block has a recessed spot for the Forster Original Case Trimmer and pilot holes for the included wood screws that come with the case trimmer.

There are holes for 8 pilots and 3 collets. The labeled model includes labels for all the pilots and collets that come in the kit plus room for one extra pilot.

There is also a spot for holding the allen key.

The photo shows the trimmer installed. I printed the no labels model and just used a sharpie to label each pilot and collet. I added the little tray for the allen key afterwards.