資料來源：https://www.seeedstudio.com/Raspberry-Pi-Relay-Board-v1.0-p-2409.html

Description
The Relay Shield utilizes four high quality relays and provides NO/NC interfaces that control the load of high current. Which means it could be a nice solution for controlling devices that couldn’t be directly controlled by IIC bus. Standardized shield form factor enables smoothly connection with the Raspberry Pi . The shield also has four dynamic indicators show the on/off state of each relay. 

Features

Raspberry Pi compatible

Interface:IIC , Three hardware SW1 (1, 2, 3) select the fixed I2C-bus address

Relay screw terminals

Standardized shield shape and design

LED working status indicators for each relay

COM, NO (Normally Open), and NC (Normally Closed) relay pins for each relay

High quality relays

Working status indicators for each relay

Specification

Compatible:Raspberry Pi ; Other main board via jumpers;

Power supply:4.75~5.5V ;

Max Switching Voltage:30VDC/250VAC;

Max Switching Current:15A ;

Frequency:1Hz;

Dimensions:91.20 * 56.15*32mm;

Technical Details
Dimensions    130mm x 60mm x 32mm
Weight    G.W 79g    
Battery    Exclude
Part List
Relay Board    1
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[Wiki]Raspberry Pi Relay Board v1.0
This wiki is for Raspberry Pi Relay Board v1.0.