This is a 5V  DC controlled 4-Channel Relay interface board, able to control various appliances and other equipment with relatively large current. It can be controlled directly by various micro-controllers.

Specifications:

• 5V DC TTL Relay Module,  4-Channels
• Each relay has a NO and a NC contact
  
• Each relay coil needs 50-60mA driver current.
• Relay can handle  250V  AC 10A ;  30V DC 10A
• Indication LED’s for Relay output status.
• 5v DC Coil supply can be isolated from TTL signal  control