1. A counter to count the quantity of objects in a single batch and the number of batches, and also can be used as length meter. 2. Can be connected with encoder, length counting wheel, proximity switch, photoelectric switch, optical sensor, capacitive switch, etc. 3. NPN and PNP sensor input switchable. 4 kinds of input mode, 6 kinds of output mode. 4. Can set alarm value for relay output. Dual 4 digits LED Display. 5. Widely applied in chemical, machine, light industry, etc. : Model: FH4-4CRNB Application Range: Machine, light industry, electronic, food, package, leather, cloth weaving industry. Function: Counting, measuring length, automatic control alarm, automatic loop alarm, etc. Input: Pulse Signal: Square Wave and Sine Wave: 5less than equal Hless than equal 30V 0less than equal Lless than equal 2V up edge active Input Impedance: equal 10Kohm Counting Speed: 30/5000CPS Counting Range: -1999-9999 Preset Range: 0.001-9999 Accuracy: +/-0.1%F.S Output: 1 Relay Contact Output Power Supply: 90-260V AC/DC Auxiliary Power: 24V DC Environment Temperature: 0-50Celsius Storage Temperature: -10-60Celsius Environment Humidity: 35-85%RH Parameter Time: 10 years Insulation Resistance: equal 10Mohm Power Consumption: less than equal 5W Contact Edge: Up edge active Hole Size: 45 x 45mm / 1.77 x 1.77inch Item Weight: 636.6g / 22.44oz Type: 4-digit Counters : Electrical colour:Black Material:plastic size:48 x 48 x80mm / 1.89 x 1.89 x 3.15inch Package Contents: 6 x Counter 12 x Bracket 6 x User Manual(English) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.