Features: 1. Human Body Infrared Sensor, Single-Channel Relay Module, Supports Sensitivity Adjustment And Delay Switch Adjustment 2. The Human Body Infrared Sensing Single-Channel Relay Module Is Programmed By The Stc8g1ko8a Chip. When The Module Senses Someone Nearby, It Turns On The Relay And Supports Dual-Mode Switching, Sensitivity Adjustment, Switch Delay Adjustment And Other Functions. Users Can Also Develop Their Own Programs Through The Extracted Programming Pins. 3. Stable Performance, Supports Human Body Infrared Sensing 4. Support Dual-Mode Switching, Select Through Jumper Cap 5. Support Sensitivity Adjustment And Relay Delay Length Adjustment Description: 1. Power Supply Port: 5V Power Supply Port 2. Human Body Induction Sensor: Bm412 3. Cascading Port: Can Be Used For Program Burning 4.Mcu:STC8G1K08A 5.5v Relay 6. Relay Output Port 7. Mode Selection: Unplug The Jumper Cap For Mode One; Plug The Jumper Cap For Mode One. 8. Human Body Sensing Sensitivity Knob: Counterclockwise To Increase Sensitivity, Clockwise To Decrease Sensitivity. 9. Relay Delay Switch Knob: Counterclockwise To Shorten The Delay Time, Clockwise To Increase The Delay Time. Material: PCB colour: As shown Package Contents: 1 x Human Body Infrared Sensor Single-Channel Relay Module 1 x 4pin Single Row Of Pins 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.