Light Sensitivity Switch Kit, Velleman.

4 Channels 5V Relay Module

Relay, as its name implies, implements a relay function. The relay can be used as a switch operated electrically through the coil to mechanically operate a switch, where it is sometimes necessary to control a circuit of another voltage and current load through a separate low power signal, such as a digital signal emitted by a mircoprocessor. Up to 30V DC and 220V AC.

One Relay Module of 1 Channel Low Level Trigger 12V.

Relé DIL Selado, compacto p/ montagem PCB

Mini Relay with 6V Output, Dual Channel.