The HS11 Feed Sensor is used to signal the chain disk system controller when the feed system is full and to shut off the chain disk system drive unit. The HS11 is mounted in the chain disk feed tube after the last drop or mounted in the last drop tube depending upon application. This kit includes the HS11 proximity sensor, mounting bracket, adjusting nuts, and hose clamps. Use the included mini driver to adjust sensitivity settings once the sensor has been installed. The proximity switch sensor tube (HSCD-900-2) can be purchased seperately and mounted on your existing chain disk feed pipe if the current installation does not have one.