This is an 433 MHz RF Transmitter-receiver pair with encoder and decoder IC. The pair consists of two modules.
Transmitter module: The transmitter part consists of an RF transmitter and an HT12E IC connected to it. This module has 4 input switches. A 8-pin DIP switch is there for address selection.
Receiver module: The receiver part consists of an RF receiver and an HT12D IC connected to it. There is a 8-pin DIP switch for address selection in this module too. To connect the transmitter module with the Receiver module, the position of the DIP switches of two modules must be same.