Description:YF-16 is a trigger counter module.It has a digital display.It can count,measure signals and inspect quality.Features:– Digital display– Long lasting– High/Low level signal trigger– Large counting range– Relay outputSpecifications:Model:YF-16Work Voltage:5V-24V DC/AC (Optional)Counting Range:1~999999 timesWork Temperature:-25~85Work Humidity:5%~95%RHSize:79.5 x 42 x 27mmWiring Port Description:NPN:NPN signal input(Negative voltage trigger)PNP:PNP signal input(Positive voltage trigger)Package Included:1 x YF-16 Trigger Frequency Counter Module1 x XH2.54-2P 20cm Cable