The SENSOR-1 Grain Drill Seed Flow Sensors are made with photocell sensors that will see through dust or chemicals. They are field tested and constructed of solid-state electronics encased in an injection-molded plastic housing and protected by a special epoxy.  The drill owner can choose between: two sensors on each end of the drill compartment to determine if ends are out of seeds and if the shaft failed to rotate; or one drill with sensors on each row to detect if a row is clogged. SENSOR-1 Grain Drill Sensors are adaptable to most types of drills.