Features SIMPLE OPERATION: PLC controller module come with simple operation, no programming required, plug and display DIRECT PLC POWER SUPPLY: No need for separate power supply, direct PLC power supply, support convenient and fast operation FUNCTION KEY AND COMMON KEY FUNCTION MULTIPLEXING: Function key and common key function multiplexing, easy to operate, realize space saving IMPACT RESISTANCE AND SCRATCH RESISTANCE: Made of good quality ABS material, possess impact resistance, scratch resistance, environmentally friendly VOLTAGE FROM DC3.5-5V: Support voltage is from DC3.5-5V, possess stable structure, excellent performance and long service life Specification: Item Type: PLC Controller Module Product Material: ABS Product Model: WSLED4 Voltage: DC 3.5-5V Package List: 1 x PLC Controller Module Note: The PLC does not respond and displays "NO PLC":A. Check whether the baud rate of the PLC is 9600;B. Check whether the electrical connection is normal or the wire sequence is correct. Package List 1 x PLC Controller Module