2Pcs 4 Channel Relay Shield 5V Module Four Way Channel Relay Control Board Expansion Board

High drive (5V or 3.3V) normally open contact closure, M3 screw positioning holes for easy installation Standard for shield interfaces and shape can continue to stack other expansion boards Onboard relay indicator (red) 5V relay module is a small current signal control power equipment commonly used electronic module, enabling high-power single-chip control devices are widely used in SCM system to make smart home project; and can be directly plugged into the compatible the use of various types of motherboards, eliminating the patch cable troubles. Note: When using the board connected to it, if USB interface is extremely high, should avoid green terminals are shorted its shell.