This is a High current driver that will take TTL signals from your Arduino, etc to drive the relays. It includes status LEDs for each input. 5V, 12V, and 24V relay options are available. This item replaces TE-010-405 and TE-010-412
This small synchronous switching step-down regulator takes an input voltage of up to 36 V and reduces it to 12 V. The board measures only 0.7″ × 0.7″ yet delivers a typical continuous output current of up to 2.2 A and features reverse voltage protection.