Material flow detect switches, used to produce a signal in flow or no flow situations at a critical point, the signal is then used to correct the error or warn the operator. The switch uses a paddle and counter weight. Typically used on conveyors, feeders, in discharge openings of bins, bunkers or hoppers. Electrical rating 20 amp at 125 VAC, nema 3 and 4 enclosure rating, dust and weather tight.