These are spacers for our Barley Cracker,  which offer finite adjustment for your crush, either finer or courser based on the plate size.  Sold in a set of 4.   Our Barley Cracker 1200 comes with a set of plates installed,  plus a size down and a size up for options is adjusting the crush.  We have this item in our store for our customers who may require some additional adjustment.  Consult your Forgeworks representative to determine which size you may need.  We document the spacer calibration that is installed with every Barley Cracker,  so we can help determine what spacer plates you will need to achieve your ideal crush.