... NPN) 4/6/8 digits display. 6 digits Multimeter for Height/Position/Length/Counting Features: 1, Various wave form pulse input ... line of machinery,food,package,etc for measuring not only height,location,length,counting,etc.,but also frequency,speed,counting at ... Signal adjustor They are widely used in industrial control and measurement field, such as machinery, electrical cabinet, power sub-station, ...