This is the index ring that is supplied with our G0704/BF20 belt drive kit. You will need the pulley kit, bearing carrier, and this index ring to complete the sub-assembly. This is a great option if you are planning on making some of the belt drive kit yourself.
Note: This is will not work with the Optimum BF20. The Optimum machines use a proximity sensor and magnets to pick up RPM from the spindle.